A man has died in a park in Adelaide.

The 54-year-old was found collapsed on a path by members of the public while on his morning walk.

What led to his death about 7.30am in the park between the Women's and Children's Hospital and O'Connell Street in North Adelaide isn't yet known.

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The Marden man was on a daily walk from Walkerville.

There was a heavy police presence today as volunteers from the SES searched the park, including going through the rubbish bins.

Detective Inspector Fraser Huntley said there was blood at the scene.

"We know that blood is from the victim but we don't know the circumstances of how that blood was found," Huntley said.

The SES conducted a line search over the entire garden.

Police said they were unable to locate anything significant and appealed for help from anyone who may have seen the man.

READ MORE: Search for father with three kids who fled Sydney crash

"We're looking for any potential witnesses or people driving past with dashcam footage to help relay the last few minutes of his life in the parklands)," Huntley said.

"He travelled on O'Connell Street as part of his normal walk, and we are seeking members of the public who were in the vicinity at that time."

A potentially deadly mosquito borne virus has been detected in Brisbane for the first time.

Health experts raised the alarm this weekend as wet weather from ex-tropical Cyclone Alfred threatened to push up infection risk.

Japanese encephalitis is now circulating amongst Brisbane mosquitoes.

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"It's not something we normally deal with here in south-east Queensland and there has been detection in mosquitoes locally," infectious diseases expert Professor Paul Griffin said.

Queensland Health warned there could be an increased risk to residents right across the region.

Recent wet weather, including from ex-Tropical Cyclone Alfred, is raising concerns the virus could spread as mosquito populations boom.

"It is something that's a bit concerning, given that we now have seen it in SEQ, it means people need to be aware," Griffin said.

The new detection came after Queensland in January recorded its first locally acquired case of the virus since 2022.

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Across the border in New South Wales, five cases have been detected in recent months.

The latest is a man in his 20s who travelled to the state's north.

Two men have already died as a result of the virus there this year.

The symptoms to watch out for include fever, headache. nausea, neck stiffness and disorientation, but most cases are mild and some people might not have any symptoms at all.

Griffin said the best way to protect yourself is to wear long sleeves, long pants, use repellent and stay inside at dawn and dusk.

Vaccines are also available for free across the country, for those at higher risk due to their job or where they live.

US President Donald Trump has said he ordered a series of airstrikes on the Houthi-held areas in Yemen, promising to use “overwhelming lethal force” until Iranian-backed Houthi rebels cease their attacks on shipping along a vital maritime corridor.

The Houthis said at least 31 people were killed.

“Our brave Warfighters are right now carrying out aerial attacks on the terrorists’ bases, leaders, and missile defences to protect American shipping, air, and naval assets, and to restore Navigational Freedom,” Trump said in a social media post on Saturday (Sunday AEDT)

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“No terrorist force will stop American commercial and naval vessels from freely sailing the Waterways of the World.”

He also warned Iran to stop supporting the rebel group, promising to hold the country “fully accountable” for the actions of its proxy.

It comes two weeks after the US leader sent a letter to Iranian leaders offering a path to restarting bilateral talks between the countries on Iran’s advancing nuclear program. Trump has said he will not allow it to become operational.

The Houthis reported explosions in their territory on Saturday evening, in the capital of Sanaa and the northern province of Saada, the rebels’ stronghold on the border with Saudi Arabia, with more airstrikes reported in those areas early Sunday.

Images online showed plumes of black smoke over the area of the Sanaa airport complex, which includes a sprawling military facility.

The Houthis also reported airstrikes early Sunday on the provinces of Hodeida, Bayda, and Marib.

The Houthi-run Health Ministry said early on Sunday (Sunday evening AEDT) that the death toll had climbed to 31, including women and children. Anees al-Asbahi, a spokesperson for the ministry, said another 101 people were wounded.

A US official said this was the beginning of air strikes on Houthi targets that are expected to continue.

The official spoke on the condition of anonymity because they were not authorised to talk to the press.

READ MORE: Search under way for missing man, 23, who fell into Brisbane River

Nasruddin Amer, deputy head of the Houthi media office, said the airstrikes won’t deter them and they would retaliate against the US.

“Sanaa will remain Gaza’s shield and support and will not abandon it no matter the challenges,” he added on social media.

Another spokesman, Mohamed Abdulsalam, on X, called Trump’s claims that the Houthis threaten international shipping routes “false and misleading.”

The airstrikes come a few days after the Houthis said they would resume attacks on Israeli vessels sailing off Yemen in response to Israel’s latest blockade on Gaza.

They described the warning as affecting the Red Sea, the Gulf of Aden, the Bab el-Mandeb Strait and the Arabian Sea.

There have been no Houthi attacks reported since then.

Earlier this month, Israel halted all aid coming into Gaza and warned of “additional consequences” for Hamas if their fragile ceasefire in the war isn’t extended as negotiations continue over starting a second phase.

The Houthis had targeted over 100 merchant vessels with missiles and drones, sinking two vessels and killing four sailors, during their campaign targeting military and civilian ships between the start of the war between Israel and Hamas in late 2023 and January of this year, when this ceasefire in Gaza took effect.

The attacks raised the Houthis’ profile as they faced economic and other problems at home amid Yemen’s decade-long stalemated war that’s torn apart the Arab world’s poorest nation.

The Houthi media office said the U.S. strikes hit a residential neighbourhood in Sanaa’s northern district of Shouab.

Residents said at least four airstrikes rocked the Eastern Geraf neighborhood there, terrifying women and children.

“The explosions were very strong,” said Abdallah al-Alffi. “It was like an earthquake.”

The Eastern Geraf is home to Houthi-held military facilities and a headquarters for the rebels' political bureau, located in a densely populated area.

The Houthis reported fresh strikes on the southwestern Dhamar province late on Saturday.

They said the strikes hit the outskirts of the provincial capital, also named Dhamar, and the district of Abs.

The United States, Israel and Britain have previously hit Houthi-held areas in Yemen. Israel’s military declined to comment.

However, Saturday's operation was conducted solely by the US, according to a U.S. official.

It was the first strike on the Yemen-based Houthis under the second Trump administration.

Such broad-based missile strikes against the Houthis were carried out multiple times by the Biden administration in response to frequent attacks by the Houthis against commercial and military vessels in the region.

The USS Harry S Truman carrier strike group, which includes the carrier, three Navy destroyers and one cruiser, are in the Red Sea and were part of Saturday's mission.

The USS Georgia cruise missile submarine has also been operating in the region.

Trump announced the strikes as he spent the day at his Trump International Golf Club in West Palm Beach, Florida.

“These relentless assaults have cost the US and World Economy many BILLIONS of Dollars while, at the same time, putting innocent lives at risk,” Trump said.

The Act Party condemned the post.

Sydney has sweated through it warmest March night in 149 years and woken to a day of extreme heat.

Beaches and water parks were packed as temperatures climbed into the high 30s today in what felt like a return of summer.

The heat was expected to linger into the evening in Sydney, with 30 degrees forecast at 9pm before a welcome cool change about midnight.

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"Today is the hottest day, and then it is the end – well, that is the hope," said Bureau of Meteorology senior meteorologist Magda Gallos-Lorenc.

Last night was Sydney's warmest march night on record, dropping to just 25.9 degrees at its coolest.

From Manly to Cronulla, beaches were busy early as the warnings rolled in.

"The heatwave season is not over yet. Summer is – heat is a silent killer," NSW Ambulance associate director for emergency management Steve Vaughan said.

"Really goes for anyone, don't be outside in the middle part of the day when it's at its hottest."

He said paramedics were braced to get about 3500 calls for help.

To avoid the heat in the west, Fairfield's water park did the job.

In the NRL, the Eels played the Tigers at Parramatta in 37 degrees.

It wasn't enough to hamper play, according to a heat stress tracker that considers a number of factors including temperature, humidity and wind.

The heat has prompted a total fire ban across greater Sydney, the central ranges, southern slopes and southern ranges regions.

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It was a sleepless night for dozens of residents in Melbourne's east who had to evacuate their homes as a bushfire tore through the area.

One property in Montrose was destroyed, while another was significantly damaged.

Kerri Maggs said it was "quite scary."

"The kids were quite frightened. Our daughter was absolutely hysterical," she said

Dozens of residents were forced to evacuate their homes.

"I went outside and the fire was like 100 metres away, the whole sky was red," local Cas Churchill said.

"The fire had flared up there were embers coming across.

"The first alert that came through on the phones was at 1.20am. Almost an hour and a half after the fire was right on our door."

Val Platt said there was little warning.

"We were in bed and I heard somebody yelling about getting out now," she said.

The fire began early yesterday afternoon and CFA crews thought they had it under control.

But with a change in conditions overnight it doubled in size, burning 40 hectares.

"The fact that the wind conditions actually picked up and with the dryness and the uphill run, it just took off this morning," deputy incident controller Mike Wilmott said.

An evacuation centre was set up at a Kilsyth reserve where 25 residents took shelter.

Today most were able to go home as the emergency warning was downgraded.

With wet weather bringing relief for crews, the clean-up began.

Even with the rain, residents in the area were still being urged to monitor conditions as they could change, but the CFA says they're hoping they'll have the fire well under control by tomorrow at the latest.

The cause of the bushfire is still being investigated.

The court told the rapist his explanation ‘smacks’ of reducing the gravity of offending.

A judge said the high-profile 501 “hit the ground running” upon arrival in New Zealand.

A search is under way for a father who pulled his children from a vehicle and fled a collision at Menai in Sydney's south.

Witnesses raced to the rescue of a woman stuck in one car before emergency services took over.

Plenty in the street heard the bang as a Mitsubishi ute flipped on its side after hitting a Mazda Sedan.

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In a matter of seconds a door opened on the ute and the father and his three children climbed out.

Vahid Tabakol said he saw them walk off.

"As I was walking towards it i see a man and three younger children walking away," he said.

Neighbours rushed to help the 43-year-old driver of the Mazda.

It was left to residents to stay by the driver's side until paramedics arrived.

"We saw the woman, she was crying and screaming and then the guy just kind of ran off with his kids," Joy Zaher said.

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Tabakol said he and other residents were worried the children might have suffered concussion and needed medical attention.

Police are continuing to search for the father.

The Mazda driver suffered only minor injuries.

The woman woke up to ‘pressure on her chest’ and thought she was ‘going to die’.