Compared to finding sunken ships in the cold abyss of the Ocean, finding a needle in a haystack is child's play.

After the "unsinkable" Titanic went down in 1912, the world searched in vain for over 70 years to find the site of the shipwreck.

It took ingenuity, decades of ceaseless work, and a covert-partnership with the US navy before the ship was finally found.

READ MORE: Alarm raised 'far too late' over missing vessel headed to Titanic

The huge steamship Titanic sank in 15 April 1912, and families of the victims wanted the bodies of their relatives retrieved.

Other groups wanted to install the shipwreck in a museum in Liverpool, England.

Within months of the Titanic's infamous Iceberg-collision, a series of far-fetched plans were hatched to raise the shipwreck from the sea-floor.

But the early efforts were deeply flawed.

One group planned to trawl the ocean floor with a massive electromagnet, attracting the massive steel structure to the magnet, then reeling it in on a giant winch.

Another proposal involved raising the Titanic by attaching inflatable balloons to her hull, then gently floating it to the surface.

These plans were abandoned out of practical concerns, but also because nobody in the world knew where the wreck was.

For decades, the search was stymied by the fact that when the ship started to go down, its distress signal wrongly reported its location.

And for decades, most had assumed that the ship sank in a single piece, instead of breaking into two halves. 

Progress on locating the Titanic built up steam after the expedition of an eccentric Texas-Oil Tycoon, Jack Grimm.

While Grimm's 1979 expedition failed to find the shipwreck, it succeeded in creating more accurate maps of the ocean floor near the likely site of wreck.

Hoping to turn his search into a documentary narrated by the famous Orson Welles, Grimm missed the site of the wreck by just 3km.

READ MORE: Titanic tourism is a thing, and it's dangerous

The breakthrough in the search would come in the mid 1980s.

Robert Ballard was an American Marine Geologist who had served in the US navy throughout his research career.

His earlier attempts in 1977 at finding the titanic ended in disaster, after the cable he was using to survey the ocean's floor shattered, losing millions of dollars of electrical equipment.

But he didn't give up.

Where previous efforts had just used sonar to scan the ocean floor, his research group the Woods Hole oceanographic institute, developed a new system of remote controlled cameras and robots attached to a submersible vehicle.

The development of the robot system was paid for by the US navy, who agreed to help Ballard search for the Titanic, on the condition that Ballard and his team first help them locate two missing nuclear submarines in a top secret mission.

The US Navy sent Ballard and his team on a classified mission to the wrecks of two previously lost nuclear submarines, the USS Scorpion, and the USS Thresher.

READ MORE: Missing billionaire's friend withdrew from earlier sub dive

Using his new system, Ballard tracked the "trail of debris" which fanned out away from the wrecks.

By manually watching the camera images, Ballard was able to determine what was man-made debris, and eventually traced the debris back to both of the missing submarines.

The Navy held up their end of the deal, and gave Ballard just twelve days remaining at the end of the Navy's allocated mission time, to travel to the possible site of the Titanic's wreck which had been narrowed down over the years.

Applying the same technique he used to locate the nuclear submarines, Ballard and his crew, set up around the clock surveillance of the cameras, as they traced the path of debris that may lead to the elusive Titanic.

Finally, at 12.48 am on Sunday 1 September, 1985, they spotted a tiny detail in a grainy image, beamed back to the ship from a depth of 3786 metres below the surface.

They had found it.

The discovery, which proved to be rust-covered steam boiler, was confirmed to be a part of the long-lost Titanic.

The next day, the main part of the wreck was found and the Titanic was seen for the first time since her sinking 73 years before.

The discovery made headlines around the world, and catapulted Ballard to overnight celebrity.

Ballard paved the way for future dives into the sunken ship, and he remains an advocate for underwater archaeology to this day.

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The race against time to find a submersible that disappeared on its way to the Titanic wreckage site has entered a new phase of desperation today as the final hours of oxygen possibly left on board the tiny vessel ticked off the clock.

Rescuers have rushed more ships and vessels to the site of the disappearance, hoping underwater sounds they detected for a second straight day might help narrow their search in the urgent, international mission.

But the crew had only a four-day oxygen supply when the vessel, called the Titan, set off around 6am on Sunday.

READ MORE: 'Got a bad feeling': Missing billionaire's friend withdrew from earlier sub dive

Even those who expressed optimism warned that many obstacles remain: from pinpointing the vessel’s location, to reaching it with rescue equipment, to bringing it to the surface — assuming it’s still intact.

And all that has to happen before the passengers’ oxygen supply runs out.

The full area being searched was twice the size of the US state of Connecticut in waters as deep as 4020m.

Captain Jamie Frederick of the First Coast Guard District said authorities were still holding out hope of saving the five passengers onboard.

“This is a search and rescue mission, 100 per cent,” he said on Wednesday.

READ MORE: Titanic tourism is a thing, and it's dangerous

The area of the North Atlantic where the Titan vanished on Sunday is also prone to fog and stormy conditions, making it an extremely challenging environment to conduct a search-and-rescue mission, said Donald Murphy, an oceanographer who served as chief scientist of the Coast Guard’s International Ice Patrol.

Meanwhile, newly uncovered allegations suggest there had been significant warnings made about vessel safety during the submersible’s development.

Frederick said while the sounds that have been detected offered a chance to narrow the search, their exact location and source hadn't yet been determined.

"We don't know what they are, to be frank,” he said.

READ MORE: 'Far too long' to begin to search for missing sub, billionaire's cousin says

Retired Navy Captain Carl Hartsfield, now the director of the Woods Hole Oceanographic Systems Laboratory, said the sounds have been described as “banging noises,” but he warned that search crews “have to put the whole picture together in context and they have to eliminate potential manmade sources other than the Titan”.

The report was encouraging to some experts because submarine crews unable to communicate with the surface are taught to bang on their submersible’s hull to be detected by sonar.

The US Navy said in a statement on Wednesday that it was sending a specialised salvage system that’s capable of hoisting “large, bulky and heavy undersea objects such as aircraft or small vessels."

The Titan weighs 9071kg.

The US Navy’s Flyaway Deep Ocean Salvage System is designed to lift up to 27,216kg, the Navy said on its website.

Lost aboard the vessel includes pilot Stockton Rush, the CEO of the company leading the expedition.

His passengers are a British adventurer, two members of a Pakistani business family and a Titanic expert.

OceanGate Expeditions oversaw the mission.

READ MORE: Years before sub went missing, letter warned of 'catastrophic' design

Authorities reported the 6.7-metre carbon-fibre vessel overdue on Sunday night, setting off the search in waters about 700km south of St John’s.

Officials have said the vessel had a 96-hour oxygen supply, giving them a deadline of early Thursday morning to find and raise the Titan.

Frank Owen, a submarine search and rescue expert, said the estimated oxygen supply is a useful “target” for searchers but is only based on a “nominal amount of consumption".

Owen said the diver on board the Titan would likely be advising passengers to “do anything to reduce your metabolic levels so that you can actually extend this".

READ MORE: Story behind world's deepest deep sea rescue

At least 46 people successfully travelled on OceanGate’s submersible to the Titanic wreck site in 2021 and 2022, according to letters the company filed with a US District Court in Norfolk, Virginia, that oversees matters involving the Titanic shipwreck.

One of the company’s first customers characterised a dive he made to the site two years ago as a “kamikaze operation”.

“Imagine a metal tube a few metres long with a sheet of metal for a floor. You can’t stand. You can’t kneel. Everyone is sitting close to or on top of each other,” Arthur Loibl, a retired businessman and adventurer from Germany, said.

“You can’t be claustrophobic.”

READ MORE: Why the odds are so heavily stacked against successful sub rescue

During the 2.5-hour descent and ascent, the lights were turned off to conserve energy, he said, with the only illumination coming from a fluorescent glow stick.

The dive was repeatedly delayed to fix a problem with the battery and the balancing weights.

In total, the voyage took 10.5 hours.

OceanGate has been criticised for the use of a simple commercially available video game controller to steer the Titan.

But the company has said that many of the vessel’s parts are off-the-shelf because they have proved to be dependable.

“It’s meant for a 16-year-old to throw it around,” and is “super durable,” Rush told the CBC in an interview last year while he demonstrated by throwing the controller around the Titan’s tiny cabin.

He said a couple of spares are kept on board “just in case”.

The submersible had seven back-up systems to return to the surface, including sandbags and lead pipes that drop off and an inflatable balloon.

Jeff Karson, a professor emeritus of earth and environmental sciences at Syracuse University, said the temperature is just above freezing, and the vessel is too deep for human divers to get to it.

The best chance to reach the submersible could be to use a remotely operated robot on a fibre optic cable, he said.

“I am sure it is horrible down there,” Karson said.

“It is like being in a snow cave and hypothermia is a real danger.”

READ MORE: Father and son duo among five people in missing Titanic submersible

Documents show that OceanGate had been warned there might be catastrophic safety problems posed by the way the experimental vessel was developed.

David Lochridge, OceanGate’s director of marine operations, said in a 2018 lawsuit that the company’s testing and certification was insufficient and would “subject passengers to potential extreme danger in an experimental submersible”.

The company insisted that Lochridge was “not an engineer and was not hired or asked to perform engineering services on the Titan”.

The firm also says the vessel under development was a prototype, not the now-missing Titan.

The Marine Technology Society, which describes itself as “a professional group of ocean engineers, technologists, policy-makers, and educators,” also expressed concern that year in a letter to Rush, OceanGate’s chief executive.

The society said it was critical that the company submit its prototype to tests overseen by an expert third party before launching in order to safeguard passengers.

The New York Times first reported on those documents.

READ MORE: What we know about the missing OceanGate sub and its expedition

The passengers lost on the Titan are British adventurer Hamish Harding; Pakistani nationals Shahzada Dawood and his son Suleman, whose eponymous firm invests across the country; and French explorer and Titanic expert Paul-Henry Nargeolet.

Retired Navy Vice Admiral Robert Murrett, who is now deputy director of the Institute for Security Policy and Law at Syracuse University, said the disappearance underscores the dangers associated with operating in deep water and the recreational exploration of the sea and space.

“I think some people believe that because modern technology is so good, that you can do things like this and not have accidents, but that’s just not the case," he said.

Timeline: How the expedition unfolded

Friday, June 16

• Polar Prince departs St John's, Newfoundland, with submersible Titan on board

Sunday, June 18

• Polar Prince reaches the submersible launch site
• One hour and 45 minutes later communications with Titan are lost
• Vessel reported overdue at 9.13pm local time (12.13pm Monday AEST)
• Rescue mission is launched involving US and Canadian coast guards

Monday, June 19

• Rear Admiral John Mauger of the US Coast Guard says the submersible has between 70 and 96 hours of oxygen left
• It's confirmed the submersible had the full complement of five people on board, including UK billionaire Hamish Harding

Tuesday, June 20

• The search area expands to almost 26,000 square kilometres
• The identities of the others on board are confirmed, including OceanGate CEO Stockton Rush, who was piloting the vessel
• "Banging" noises are heard from beneath the ocean's surface

Wednesday, June 21

• Further banging noises are heard as all available search assets are redirected to that area
• The estimate oxygen supply available to those aboard the sub dwindles to under 20 hours

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Police are appealing for witnesses after a man forced a woman out of a parked car and threw her into oncoming traffic in Perth, forcing a truck to swerve out of her way.

A silver Holden Commodore sedan was captured on camera pulling over into the emergency lane of Roe Highway heading north at around 8.30pm on Saturday, February 25.

A man inside the vehicle forced a woman out of the car, then forcibly launched her into the left lane of traffic on the 100km/h highway.

READ MORE: Bus perched on concrete barrier after crash in Sydney

The driver of a truck in the left lane managed to swerve to avoid hitting the woman, despite another vehicle being in the right-hand lane at the time.

The man then forced the woman back into the Commodore and drove away.

West Australia's Sex Assault Squad detectives are investigating, and have asked the driver of both the truck and the right-lane vehicle to come forward.

READ MORE: Missing billionaire's friend withdrew from earlier OceanGate dive

Police say the man is known to the woman.

Anyone with information or who has dash-cam vision relating to the incident is asked to contact Crime Stoppers on 1800 333 000 or via www.crimestopperswa.com.au.

If you or someone you know is impacted by sexual assault, domestic or family violence, call 1800RESPECT on 1800 737 732 or visit 1800RESPECT.org.au. In an emergency, call 000.

Readers seeking support can contact Lifeline on 13 11 14 or beyond blue on 1300 22 4636.

Every winter armies of native spider crabs gather in the shallow waters of Melbourne's Port Phillip Bay, in what is one of the world's most enduring ocean mysteries.

Within months, the crustaceans are gone, and disappear into the depths of the sea and no-one really knows where they go.

Researchers are still working out exactly why the phenomenon occurs, but hold several theories as to what may be going on.

READ MORE: Despite record-breaking chill, this winter is already warmer

Mystery surrounds aggregation

There is little scientific data collected around spider crabs, Deakin research fellow in spider crab ecology Dr Elodie Camprasse told 9news.com.au.

But she believes the species head to the shallow waters to crawl out of their shell, a process that leaves them extremely vulnerable.

"They need to grow out of their shell and harden a new shell," Camprasse said.

"We think that process takes a day or two. During that time, the spider crabs are soft, which means they are vulnerable to predators. That's the reason why we think they come together in such big numbers.

"If they are in the middle of a spider crab pile, it could reduce their chance of becoming a meal for predators (including) stingrays or smaller sharks. They try and munch on them often as they are easy targets.

"Their shell acts as an armour."

READ MORE: What could possibly have gone wrong with missing submersible?

Researchers observed more than 50,000 crabs gather over a three day period last year in the bay.

The crabs, usually orange to red-brown can reach 16cm across their shell and 40cm across their legs.

They usually generate the most attention during the winter months, when they come together also known as "aggregation".

Spider crabs have also been observed at different locations in Victoria, including on the Mornington and Bellarine peninsula.

"We don't know much at all about how they choose the locations or what might trigger the aggregations," Camprasse said.

"Some people think it might be related to water temperature or the moon cycle. We just don't have enough data to say why." 

READ MORE: Rare deep sea shark trawled from depths – but that's not only surprise

Community led research 

A team of scientists at Deakin University hope the public can help learn more about the species through community led research.

Although the main project is based on the Mornington Peninsula, the citizen science program seeks the assistance of everyone, from recreational fishermen, divers, charter tour operators to collate data on the aggregation.

"These aggregations seem to happen at random times," Camprasse said.

"Unlike some citizen science programs, we need our members to record both when they see spider crabs, but also when they don't, so we can try and establish a pattern of when the aggregations happen."

She said until more research is funded into the species, they will continue to remain a mystery.

"What fascinates me is how little we know about this species, they usually come together in deeper water and away from the shore, but this phenomenon has been potentially happening for more than decades," Camprasse said.

"For them to come together in shallow water, like you can see them and yet there are so many answers we don't have about their basic biology, it is very interesting."

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A friend of one of the passengers stranded on the five-person submersible missing in the remote Atlantic Ocean has spoken about why he opted out of a similar OceanGate trip.

Explorer Chris Brown, a friend of UK billionaire Hamish Harding, said he had paid a deposit to go down on an OceanGate trip but ultimately backed out.

"What explorers do when they take up an expedition, they take a grasp of all the risks in the expedition, to try to mitigate those that they can, they might use different equipment and might bring in the use of experts or mitigate risks by changing the time of year that you do your expedition," he told Today.

READ MORE: New noises heard as search for Titanic sub deepens, oxygen dwindles

"I had a look at it, it just seemed quite a few risks that were outside my control."

Brown said OceanGate had a record of missing depth targets and that parts of the submersible seemed, to him, "a bit ad hoc".

"I just generally got a bit of a bad feeling, so I withdrew from the operation," he said.

READ MORE: CCTV captures moment tyre ricochets through Adelaide shop

More has emerged in recent days regarding criticism of OceanGate and its operations, particularly regarding its ocean trips.

"The fact that they flatly refused to try and get certification for the vessel didn't bode well," Brown said.

But he said the main issue at the moment was the search for five people who were in extreme danger.

"I just want to see these guys rescued," he said.

He described Harding as "fiercely intellectual, very grounded, not prone to panic".

"Whatever the situation, he would be working out the optimal route and try to improve the chances of being found," Brown said.

READ MORE: China rift 'cracked open' after Biden 'dictator' claims

But he warned that even if the vessel had bobbed to the surface, the occupants were still in danger.

"Even if it's come to the surface, it still needs opening from the outside so oxygen would still be an issue," he said.

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Brooke Rowlands was on the cusp of starting a new life in Melbourne when she stepped off a kerb and everything turned black.

The next thing the social worker remembers is being confused that her office was on its side and wondering why a woman was standing over her, telling her to lie down when she tried to get up.

She did not know then that she was the victim of a hit-and-run and had just been flung through the air like a "rag doll" in front of her colleagues on Devon St West in New Plymouth.

READ MORE: China rift 'cracked open' after Biden 'dictator' claims

The force of the impact was so violent it tore her shoes apart, one sole remaining stuck in place at the point of impact. In a split second the 27-year-old had suffered a host of horrifying injuries.

In her right leg her tibia and fibula were badly broken and the humerus of her right arm was smashed, causing significant nerve damage. Her head was bleeding, her legs cut and she was concussed.

With the adrenalin surging through her body Rowlands had no idea how broken she was. Her biggest concern was for her teeth she'd worn braces for years to straighten.

"The woman said to me, 'don't worry about your teeth, we can get you new teeth'," she said.

Hit three months ago she faces many more months of rehabilitation to get back to where she was before the driver ran a red light ploughed straight into her and failed to stop.

Unable to work and with limited mobility, the fiercely independent woman is angry at the sense of injustice she is left with after being hit simply using a signal-controlled crossing.

READ MORE: New noises heard as search for Titanic sub deepens, oxygen dwindles

Rowlands wants to share her story to give a voice to victims, to ensure they are not forgotten.

She is especially incensed the driver, who was arrested one day after the hit-and-run, was able to plead guilty last week to a charge of careless driving, rather than dangerous driving, thereby ending any chance of a lengthy stint in prison.

"As my Dad said, you don't get a reduced recovery time," she said.

The turn of events ended any hope she'd participate in restorative justice, a process designed to give offenders genuine understanding of the impact of their crimes and help victims feel heard.

"He's not sorry for what he did or else he would have owned up to it straight away," Rowlands said. "He's taken enough from me, I don't owe him anything."

As well as the pain of her injuries, the driver took her independence, her future and her dignity.

READ MORE: CCTV captures moment tyre ricochets through Adelaide shop

Her right arm and leg remain heavily bandaged. She needs a crutch to walk short distances, uses a wheelchair for anything outside the house.

People stare at her wherever she goes, making her both self-conscious and angry she's even in the situation.

"I just want to say this wasn't my choice. I didn't do it to myself. I didn't do anything stupid. I got hit by a car on my way to work."

There is also an irony in her situation that offers a rare light moment.

Rowlands was supposed to be living in Melbourne now. Her flights were booked for April 29 and she had a job lined up as a rehabilitation consultant for getting people back to work after vehicle crashes.

She is aware there is a silver lining in now being more qualified for the role than ever, even if she'd prefer to have avoided such experience. Rowlands also knows things could have been much worse.

Though she was hit by a car going 60kmh, she somehow wasn't killed, she somehow avoided a serious head injury and there is a good chance most of her injuries will heal, though she carries a gnawing anxiety over whether she will regain full use of her right hand, which hangs limp without support.

"And I am right-handed so that is scary," she said.

The company in Melbourne is also holding her job open, and she is deeply grateful for the love and help her family and friends have provided when she needed it most.

"It's made me really angry but I've tried to channel my anger into things I can control," she said.

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Two Australian capitals have made major comebacks in 2023, making it into the top four most liveable cities.

The family of the British billionaire missing in a submersible in the remote Atlantic Ocean say tour operator OceanGate waited too long before contacting authorities.

Rescuers are racing against time to find the five-person vessel today before oxygen supplies run out.

New footage from today shows Canadian military aircraft and naval vessels in the search for the Titan, which vanished on Sunday with five people aboard, en route to view the wreckage of the Titanic.

READ MORE: Titanic sub firm's choices 'subject passengers to potential extreme danger': Lawsuit

It comes as more "banging" noises detected overnight sparked hope the five adventurers on board the Titan are still alive, but even those who expressed some optimism warned many obstacles remained.

And as time dwindles, the family of passenger Hamish Harding, a UK billionaire, have spoken out about the eight-hour interval between when the Polar Prince, which launched the sub, lost contact with it, and when the vessel notified the US Coast Guard.

His cousin Kathleen Cosnett told the UK Telegraph it had taken "far too long" to sound the alarm.

"I would have thought three hours would be the bare minimum," she said.

She said the situation was "very frightening".

At a briefing on Wednesday afternoon (Thursday morning AEST), US Coast Guard first district Captain Jamie Frederick stressed the sounds were "inconclusive".

"We need to have hope. Right?" he said, saying the mission was still "100 per cent" a search and rescue.

"I can't tell you what the noises are.

"But what I can tell you is, and I think this is the most important point, we're searching where the noises are and that's all we can do at this point."

READ MORE: What could have gone wrong with missing submersible?

One expert told CNN pinpointing the source of the noise was like trying to locate a particular drum in a packed and raucous stadium.

Rick Murcar, who is the international training director for the National Association of Cave Divers and the owner of Aquatic Adventures of Florida Inc., explained that sound travels faster in the water — which is making it more challenging for rescuers to pinpoint where it is coming from.

Things like the currents can deflect the sound so that it appears like it is coming from miles away from where the actual source is.

"Picture a massive stadium that has a roof on it, and you have an aircraft flying over top and it drops sensors down to listen to the sound inside that stadium," he said.

The person inside the stadium is playing a snare in a constant, beating pattern, in addition to all of the other drums he has, Murcar said.

READ MORE: Story behind world's deepest deep sea rescue

Several more search vessels were on the way to a search zone four kilometres deep and about twice the size of Greater Sydney.

That included a doubling of the number of vessels on the surface to 10 and a "state-of-the-art" remote-operated vehicle from France due on Thursday morning (Thursday night AEST).

Key to the search are camera-equipped remote-operated robots, which are designed to scan the seafloor in real-time at depths other vessels can't reach. Two were operating in the area Wednesday and more were on the way, officials said.

Other equipment on the way included specialised salvage system equipment capable of hoisting "large, bulky and heavy undersea objects such as aircraft or small vessels," the US Navy said in a statement.

Lost aboard the vessel are pilot Stockton Rush, the CEO of the company leading the expedition. His passengers are a British adventurer, two members of a Pakistani business family and a Titanic expert.

Rescuers faced a race against the clock because even under the best of circumstances the vessel was expected to run out of oxygen on Thursday.

READ MORE: Ernest Hillier, one of Australia's oldest chocolate companies, collapses

Woods Hole Oceanographic Institution director Carl Hartsfield said ocean noises were "complex" and would need to be analysed closely by experts.

"The noises have been described as banging noises, but again, they have to put the whole picture together in context and they have to eliminate potential manmade sources other than the Titan," he said.

" … I can tell you from my experience with acoustics that there are sounds, biologics, that sound man-made to the untrained ear but I can assure you that the people listening to these tapes are trained. 

"There are a lot of vessels in the area and they each make noise, right, so all of that has to be eliminated and its analysis over time."

The Coast Guard statement about detecting sounds underwater across two days came after Rolling Stone reported that search teams heard "banging sounds in the area every 30 minutes".

The report was encouraging to some experts because submarine crews unable to communicate with the surface are taught to bang on their submersible's hull to be detected by sonar.

"It sends a message that you're probably using military techniques to find me and this is how I'm saying it," said Frank Owen, a submarine search and rescue expert.

"So, that's really encouraging if that's the case."

In addition to an international array of ships and planes, an underwater robot had started searching in the vicinity of the Titanic and there was a push to get salvage equipment to the scene in case the sub is found.

Even if the vessel's location can be confirmed, rescuers will need to reach it with equipment, to bring it to the surface — assuming it's still intact — before the passengers' oxygen supply runs out.

The area of the North Atlantic where the Titan submersible went missing on Sunday is prone to fog and stormy conditions, making it an extremely challenging environment to conduct a search-and-rescue mission, said Donald Murphy, an oceanographer who served as chief scientist of the Coast Guard's International Ice Patrol.

And questions remain about how teams could reach the lost submersible, which could be as deep as about 3800 metres below the surface near the watery tomb of the historic ocean liner.

Newly uncovered allegations also suggest there had been significant warnings made about vessel safety during its development.

Authorities reported the carbon-fibre vessel overdue on Sunday night, setting off the search in waters about 700 kilometres south of St John's.

The submersible had a four-day oxygen supply when it put to sea about 6am on Sunday, according to David Concannon, an adviser to OceanGate Expeditions, which oversaw the mission.

– Reported with AP and CNN

Timeline: How the expedition unfolded

Friday, June 16

• Polar Prince departs St John's, Newfoundland, with submersible Titan on board

Sunday, June 18

• Polar Prince reaches the submersible launch site
• One hour and 45 minutes later communications with Titan are lost
• Vessel reported overdue at 9.13pm local time (12.13pm Monday AEST)
• Rescue mission is launched involving US and Canadian coast guards

Monday, June 19

• Rear Admiral John Mauger of the US Coast Guard says the submersible has between 70 and 96 hours of oxygen left
• It's confirmed the submersible had the full complement of five people on board, including UK billionaire Hamish Harding

Tuesday, June 20

• The search area expands to almost 26,000 square kilometres
• The identities of the others on board are confirmed, including OceanGate CEO Stockton Rush, who was piloting the vessel
• "Banging" noises are heard from beneath the ocean's surface

Wednesday, June 21

• Further banging noises are heard as all available search assets are redirected to that area
• The estimate oxygen supply available to those aboard the sub dwindles to under 20 hours

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An Adelaide butcher's shop had to shut what was left of its doors for the day after dealing with an unpredictable customer – an errant, hurtling truck tyre.

A truck travelling along Goodwood Road in Goodwood in the city's inner south about 8am yesterday lost its rear left tyre in a freak accident.

The tyre smashed through the front of Goodwood Quality Meats, just metres from a primary school and a pedestrian crossing.

READ MORE: Ruthless Maroons hammer Blues to clinch Origin series

"We heard this almighty bang and unfortunately a truck tyre had come off the axle or something like that and rammed into our shop," manager Luke Leyson told 9News.

"It smashed our shop window, a new cabinet that we put in, our door that's been there since the 1960s."

The truck scraped along the road for 30 metres on three wheels before it managed to stop.

Leyson said the driver was "a bit upset".

READ MORE: Father who killed toddler could be released back into community



"It was a freak accident, no one's fault, and he's done the best he could," he said.

The store had to shut up shop for the day, with shattered glass through most of the meat.

The damage bill has been estimated at roughly $12,000.

"It's taken its toll on the business a bit but we're just happy no one got hurt," Leyson said.

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A strong explosion has hit a building in Paris' Left Bank, leaving at least 24 people injured — four critically — and igniting a fire that has sent smoke soaring over city monuments and prompted the evacuation of buildings, police say.

Police were investigating suspicions a gas leak caused the Wednesday afternoon (Thursday morning AEST) blast, which caused the building's facade to collapse and left authorities searching for two people who might be trapped inside.

The facade of a building in the fifth arrondissement, or district, collapsed and emergency services were working to determine if anyone was still inside, a Paris police official said.

READ MORE: Titanic sub firm's choices 'subject passengers to potential extreme danger': Lawsuit

The explosion hit near the historic Val de Grace military hospital.

Sirens wailed as ambulances passed through the neighbourhood, but residents started to move freely again on the previously cordoned off street, rue Saint-Jacques. Associated Press reporters said smoke had stopped pouring out of the building where the explosion occurred.

The fire was contained Wednesday evening (Thursday morning AEST) but not yet extinguished as Paris bars and restaurants celebrated the summer solstice with a citywide annual music festival.

Some 270 firefighters were involved in putting out the flames and 70 emergency vehicles were on the scene.

Paris police chief Laurent Nunez said the building housed a private school, the Paris American Academy. The school was founded in 1965 and offers teaching in fashion design, interior design, fine arts and creative writing.

A Paris police official told the AP 24 people were injured, including four in a critical condition and 20 with less severe injuries. The official said the injuries were sustained mainly when people were blown off their feet by the blast.

Jema Halbert, who owns a butcher's shop close to the explosion site, said she went upstairs to fetch something.

"I heard a 'boom'. … So then I went downstairs, where I found my husband in shock, dust by the till and I thought, wait, there's a problem," she said.

"So I stepped outside and I saw big flames and I said, it's impossible. I called my daughter. She was crying. She was shocked."

Edouard Civel, deputy mayor of the 5th arrondissement, attributed the explosion to a gas leak but other officials were more cautious.

A judicial official said a gas explosion was one of the possible causes under investigation.

District Mayor Florence Berthout said on French TV channel BFM that firefighters were searching for two people believed to have been inside the building at the time of the blast.

"The explosion was extremely violent," she said, describing pieces of glass still falling from buildings.

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Renowned Greek-French filmmaker Costa-Gavras was among the witnesses at the scene .

"A huge noise and the house was shaken like this," the 90-year-old told the AP, visibly rattled.

"We thought, what is going on? We thought it could be the sky (a storm). … It's not something to laugh about."

Paris Prosecutor Laure Beccuau said an investigation was opened into aggravated involuntary injury and the probe would examine whether the explosion stemmed from a suspected violation of safety rules.

Beccuau said investigators would seek to "determine whether or not there was failure to respect a rule or individual imprudence that led to the explosion".

Nunez, the Paris police chief, said firefighters prevented the fire from igniting two neighboring buildings that were "seriously destabilised" by the explosion and evacuated.

The explosion blew out several windows in the area, witnesses and the police chief said.

With more than two million people densely packed within the city limits and historic, sometimes ageing, infrastructure, Paris is not a stranger to gas explosions.

A January 2019 blast in the ninth district killed four people and left dozens injured.

Achille, a student, said he was in a building about 100 metres from the explosion.

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"I was sitting on the windowsill, and we moved two metres away from the window, carried by a small blast (from the explosion) and huge fear," he told BFM television, without stating his last name.

"We came down (from the building) and saw the flames," he said.

"The police gave us great support and we evacuated quickly."

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