A new survey has found Australians' trust in Coles and Woolworths has plummeted after the supermarket giants suffered the worst reputational damage seen in seven years.

Coles fell from the country's fifth most trusted brand in December to the ninth most distrusted brand in March, according to Roy Morgan.

During the same period, Woolworths dropped from Australia's second most trusted brand to 34th.

READ MORE: Can the Reserve Bank squash inflation with just a threat?

Roy Morgan chief executive Michele Levine said that in the past seven years of tracking data, there had never been a reputational crash as dramatic as what the supermarket duopolies have experienced.

"Sadly, this is just the beginning. Our data reveals even more dramatic reputational declines in the coming months," she said in a statement.

Coles and Woolworths have been the centre of a parliamentary inquiry into supermarket price gouging during the cost of living crisis.

The pair have been accused of profiteering.

In the last financial year, Coles posted a $1.9 billion profit while Woolworths posted $1.62 billion.

Meanwhile, the price of food and non-alcoholic beverages grew by 4.4 per cent in the year to January.

These have all contributed to the significant drop in trust, Roy Morgan said. 

READ MORE: What you're going to get in next week's federal budget

Levine said this was in direct contrast to the soaring reputational trust the supermarkets gained after stepping up during the pandemic to keep stores open and safe.

She said Coles and Woolworths were now paying the price for failing to recognise cost of living as another "genuine crisis".

"Despite their plummeting trust and soaring distrust, both supermarket giants appear to be performing at the checkout, but trust and distrust measures are what we call 'lead indicators'. In other words, they foreshadow what is to come," she said.

"Woolworths' share price, for example, has already fallen 22.5 per cent since mid-June last year.

"Distrusted brands become fragile, making them targets for smart competitors like Aldi and other overseas competitors looking for new territories."

Roy Morgan surveys about 2000 Australians every month to measure levels of trust and distrust of about 1000 brands across 26 industries. 

The Reserve Bank doesn't think it'll have to increase interest rates again. It certainly doesn't want to. But it might have to, so you should be prepared.

That was, broadly speaking, the message from Governor Michele Bullock yesterday after her board kept rates on hold at 4.35 per cent – even though they discussed what would have been a 14th hike.

"We don't think we necessarily have to tighten again," she said in her media conference following the rates decision.

READ MORE: Interest rates on hold despite RBA discussions about another hike

"But we can't rule it out. If we have to, we will.

"If we really think that inflation is going to be persistent and significantly above our forecasts, we will tighten again."

That threat of hike number 14 was kept very much on the lectern throughout Bullock's press conference. The board would be "vigilant" and "very watchful" because higher inflation would be "more costly".

"I would say to people who are struggling that I understand they are struggling. Part of the reason they are struggling is not just interest rates, though," she said.

READ MORE: What you're going to get in next week's federal budget

"It's inflation.

"The best thing that I can do for them is to try and get inflation back down so that they don't have to worry about the prices of their everyday things continuing to go up.

"That's the best thing I can do for them. I understand the interest rates hurt, but that's the tool I've got and that's the best thing I can do for them."

But there's one other weapon Bullock has in her arsenal, and she used it to full effect yesterday.

"There's more in the Reserve Bank of Australia's toolkit than just interest rates," Moody's Analytics economist Harry Murphy Cruise said.

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"When the RBA speaks, households listen. And (the) statement by the board speaks volumes.

"The board has taken a slightly more hawkish tone this month… keeping the prospect of a future rate hike in play."

While some of that is a genuine willingness to raise rates if needed, he says it also serves another purpose.

"The threat of future rate hikes can sometimes be enough to dampen demand without the need to actually pull the trigger," Murphy Cruise said.

"Indeed, we think the most likely outcome is for rates to stay where they are until December."

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At any rate, inflation is likely going to be higher for longer than what was thought a few months ago. The RBA's short-term annual forecasts, up to 3.8 per cent, say as much.

"A really big part of that" is perennially problematic petrol prices, Bullock said yesterday, but there are other culprits.

"Australia is joining a growing list of economies proving that the final mile of bringing down inflation is the hardest… Service inflation, the main culprit holding back progress, jumped 4.3 per cent in the March quarter," Murphy Cruise said.

"It was buoyed by the biggest jump in insurance premiums in 23 years, rents growing at their fastest annual pace since 2009, and education fees experiencing their steepest quarter-on-quarter rise in 12 years.

"What is more, a chunk of progress on inflation has come from temporary government rebates that will eventually unwind."

Moody's has pushed back its forecast of when inflation will be back on target by three months, until June 2025. The RBA reckons it'll be closer to the end of that year.

But as for a change in interest rates? Maybe the threat of a rise will be enough.

Students are set to be some of the big winners from this year's federal budget thanks to a number of cost-of-living relief packages announced by the government.

While Treasurer Jim Chalmers won't unveil the budget until May 14, changes to HECS-HELP indexation and a new $320-a-week payment for students on placement will both form a central part of it.

Chalmers has otherwise tried to temper expectations, warning "there will not be big cash splashes in the budget, simple as that", but there are still some significant policies aimed at alleviating hip pocket pressures on the way.

Some, like stage 3 tax cuts have already been announced, while the government has hinted at others without providing many details. This is what you can expect in the federal budget – and how much you can expect to benefit from those plans.

READ MORE: Almost $3 billion of student debt to be wiped in federal budget

Student debt relief and placement support

Both Prime Minister Anthony Albanese and Chalmers had flagged cost-of-living relief for students well in advance of the budget, and two policies have since been announced, with more likely to come on May 14.

Announced on May 6 was Commonwealth Prac Payment – a support payment for teaching, nursing, midwifery and social worker students doing workplace placements for their degrees.

It will provide $319.50 per week to students during their clinical and professional placements in an attempt to combat "placement poverty".

It will be means tested, with the government expecting it to be paid to around 73,000 students, although it won't come into effect for more than a year – it'll first be available on July 1, 2025.

READ MORE: PM unveils $925 million fund for domestic violence survivors

The other measure is far more wide-ranging: changing the way HECS-HELP debt is indexed.

Student debt has previously risen in line with inflation every year on June 1.

That will now change, with debts to instead be indexed to whichever is lower out of inflation or the wage price index.

The move was recommended by the Australian Universities Accord review, and means students aren't faced with a debt that's increasing faster than their earning power through no fault of their own.

It will also be backdated to June 1, 2023, so everyone who was hit by the record 7.1 per cent increase thanks to high inflation will see their debt reduced, with 3.2 per cent indexation applied.

It will also reduce this year's projected hike which, instead of coming in at 4.7 per cent, will now be 4 per cent.

READ MORE: Calls to improve housing affordability, save billions in one move

The government says the move will provide about $3 billion in relief to the more than 3 million people who have student debt.

We also know there will be further changes to higher education included in the budget, with Education Minister Jason Clare flagging more responses to the Universities Accord to be unveiled on May 14.

What that will actually be, we don't know.

The review made 47 different recommendations, ranging from establishing a $10 billion future fund to invest in the sector, to changing the university funding model, and increasing the number of fee-free places.

READ MORE: Federal government commits $160m to establish national firearms register

Stage 3 tax cuts

The government's signature tax policy will form a key part of this year's budget.

Announced in January and passed by parliament the next month, the policy reworks the former government's stage 3 tax cuts to direct more of the benefit towards low- and middle-income earners – although Australians on high salaries will still receive a tax cut.

Done to alleviate cost-of-living pressures, as well as to at least partly address bracket creep, the cuts lower the tax rate for the lowest two brackets (so we're all paying less tax on that income), and raise the threshold for the two highest brackets (so you need to earn more to be taxed at those higher rates.

READ MORE: Defence spending gets $50 billion boost over next decade

This is slightly different to the original stage 3 tax cuts under the Morrison government, which would not have lowered the tax rate for those first two brackets.

They would also have abolished the 37 per cent bracket and raised the threshold for the top bracket to $200,001.

The new version of stage 3, which comes into effect on July 1, will see every taxpayer get a cut.

Someone on the average income of around $73,000 will get $1504, but exactly how much you'll get depends on how much you earn:

The cost to the budget of the policy is estimated to be about the same as the previous iteration of stage 3: $105.7 billion by 2027–28.

Chalmers said there would also be tax reform beyond the stage 3 cuts.

"There'll be some other tax changes as well," he told ABC radio.

"In all of the budgets we've done so far, there has been modest but meaningful tax reform… people should expect to see more of that on Tuesday."

Those exact measures haven't been announced, but Chalmers ruled out changes to the housing sector such as negative gearing, instead saying they would be tied to the Future Made in Australia program, suggesting a focus on business and investment.

READ MORE: The opposition wants 'mature debate' about nuclear. This is what experts say

Welfare support increases

Australians on welfare are likely to receive some kind of a boost to their payments.

A week from budget day, Chalmers was asked about the timing of a potential increase to the JobSeeker rate, which was recommended by the Economic Inclusion Advisory Committee (EIAC).

"There will be additional steps in this budget which are conscious of the recommendations that that important, well-regarded, well-informed committee, has put to us," Chalmers said.

What those additional steps are, though, is a bit of a mystery. It could be a JobSeeker raise – the EIAC called for it to be bumped up to 90 per cent of the aged pension.

That would see it jump from the current $762.70 per fortnight for single people up to $1004.67 – a rise of $121 per week or about $17 per day.

But the EIAC made 21 other recommendations, including an increase to rent assistance payments, investing in social and affordable housing for Indigenous people, and overhauling the employment services system.

READ MORE: Welfare boost set to be included in next week's budget

Superannuation on paid parental leave

Under another policy that's already been announced, superannuation will be paid on government-funded parental leave.

While it will help address the 25 per cent less super that women have, on average, compared to men, it won't make a difference this year – the policy is due to come into effect on July 1, 2025.

As for how much it'll cost, we don't know that either. A figure will be included in the budget on May 14.

READ MORE: Security guards to double at Centrelink after stabbing

Energy bill relief

Much like with student debt, there have been some hints from the government that energy bill relief will continue in this year's budget.

On April 4, Albanese touted an existing policy, introduced in the 2023-24 budget, that gives eligible families up to $500 off their power bills and eligible small businesses up to $650.

"Our government understands that for small business – as for Australian families – energy bills remain a source of financial pressure," he said.

"That's why the energy bill relief package I negotiated with the states and territories delivered up to $650 in savings for around 1 million small businesses, along with 5 million families.

"And as we put together next month's budget, small businesses and families will again be front and centre in our thinking."

Energy bills are actually set to go down, or at least stay fairly stable, for much of the country from July 1 – a far cry from last year's big hikes.

But Albanese's comments indicate the current energy bill relief could be extended for another year.

READ MORE: How Australia brewed the perfect storm to put craft beer out of business

Anti-domestic violence measures

Just under two weeks before the budget, the government announced $925 million in funding for payments to support people fleeing abusive relationships amid nationwide outrage about the spate of violence against women.

Those escaping violence will be eligible to receive up to $5000 in financial support, along with access to safety assessments and referrals to support pathways, as of July 1, 2025.

The government also announced $6.5 million for a trial of online age verification technology to stop young people from viewing inappropriate material, including pornography and violence, to combat the spread of toxic attitudes towards women.

READ MORE: Single mum's $200 bill shock in cost-of-living crisis

Finance Minister Katy Gallagher, who is also the federal minister for women, flagged there could be more announcements included in the budget, while also pointing to its national plan, which was established in 2022.

"We're committed to the national plan, that sets out our overarching goal to end violence against women and children in a generation," she said.

"It has already got $2.3 billion attached to that plan. We are making additional investments to that, you'll see some of that in the budget."

READ MORE: The government says it's cracking down on toxic views towards women online. This is what that means

What else we know will be in the budget

There's a range of other measures we know will form part of the federal budget, including:

• A $50.3 billion spending boost for the military as the government pushes defence spending up to 2.4 per cent of GDP.
• $314 million across the next two years to improve safety at Services Australia centres, including almost doubling the number of security guards.
• $1.9 billion for 14 new and two existing infrastructure projects in Western Sydney, including a series of road upgrades.
• $160 million to establish a national firearms register.
• Investing $519 million into the Future Drought Fund for programs that help farmers and regional communities prepare for and mitigate the effects of drought, as well as building climate resilience.
• $100 million in construction and upgrades for bike and walking paths under a new active transport fund, to come into effect on July 1, 2025. 
• $90 million to address the skilled construction worker through 20,000 new fee-free TAFE and VET places and pre-apprenticeships.

Susan Buckner, best known for playing peppy Rydell High School cheerleader Patty Simcox in the 1978 classic movie musical Grease, has died. She was 72.

Buckner "died peacefully" on May 2 and was "surrounded by loved ones," according to a statement sent to CNN on Tuesday from her family's publicist Melissa Berthier. A cause of death was not provided.

"Susan will be remembered for her kindness, generosity and unwavering commitment to making a positive impact in the lives of others," Berthier's statement read.

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"Her effervescent spirit will continue to inspire generations of performers and fans alike."

The Washington native played Simcox, the energetic and bubbly cheerleader who served as the embodiment of school spirit at Grease's fictional Rydell High, alongside Olivia Newton-John's iconic character Sandy.

Prior to Grease, Buckner was a pageant queen in 1971, when she was crowned Miss Washington, later representing the state of Washington in the Miss American pageant.

In the early 1970s, she went on to appear on episodes of The Dean Martin Show, Police Woman and Switch. Buckner later put her musical talents on display while appearing as a dancer and synchronised swimmer on The Brady Bunch Variety Hour in 1976.

Throughout the late 1970s and into the 1980s, Buckner appeared in a number of TV series including Starsky and Hutch, The Love Boat, and The Hardy Boys/Nancy Drew Mysteries, and co-starred in the ABC series When the Whistle Blows alongside Dolph Sweet.

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She also appeared on the big screen in the 1981 Wes Craven-directed horror film Deadly Blessing opposite Sharon Stone. Her final credit, according to her IMDb page, is playing a news reporter in the 1989 film Police Academy 6: City Under Seige.

In her later years, according to a biography provided by Buckner's publicist, she stepped away from Hollywood to focus on being a mom to her two children, Adam Josephs and Samantha Mansfield. Buckner also became a theatre instructor for young children and taught dance in Coral Gables for nearly a decade.

She is survived by her partner Al, her sister Linda, her two children and four grandchildren.

"She was magic. She was my best friend. And I will miss her every day," Mansfield said in a statement shared with CNN.

"I was lucky I had such a lighting rod of a mother and now I have her as an angel."

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Verifying your identity is something we all have to do fairly regularly, but it's about to fundamentally change as Australia passes legislation for a national digital ID.

The laws passed the Senate in late March and will go before the lower house in the upcoming parliamentary sitting period, although the ID itself (called myGovID) is already up and running.

So how do digital IDs work, why do we need them, and is Australia's system actually going to be any good? This is what you need to know.

READ MORE: The federal budget is almost upon us. This is what you can expect from it

What is a national digital ID and how do they work?

Not to be confused with digital licences – which are just a computerised version of a physical card – a digital ID is a system that allows Australians to quickly and easily identify themselves without having to provide "points" of ID to a range of organisations.

"I often talk about avoiding that painful process of collecting 100 points of ID – having to scan them, get them printed and get some undecided back of them and like exactly all of that physical paperwork and face to face interactions," Lauren Perry, a responsible policy specialist at the UTS Human Technology Institute, told 9news.com.au.

"You can get them verified once and then you're good to go to use them online for multiple interactions."

In essence, the digital ID acts as a go-between between the user and the organisation that wants to verify their identity.

READ MORE: Your phone in SOS mode could be a sign of something far more sinister

"I use the analogy of it's like going to the pub and someone being your wingman," University of the Sunshine Coast computer science lecturer Dr Erica Mealy told 9news.com.au. 

"It's like setting that up through an app on your phone. 

"So when you go to an organisation, you type in their number that they give you, which is registered with the government scheme, into an app that you have on your phone. 

"And then it contacts that organisation through the pathway that they have approved with the government and says, 'Yes, we've got Erica's app you, I can verify this is Erica'."

At the moment, the app that does that is the government's myGovID, but private providers could get involved after the legislation passes.

"The thing I like about this scheme is they are talking about also having third parties involved," Mealy says. 

"If you look at someone like MasterCard or Visa, they have a vested interest in making sure that they don't have fraud in the network."

READ MORE: Australia's 3G network is shutting down. This is what you need to know

Why create a digital ID? What are the benefits?

In short? Security.

"The current system is plagued by identity theft, fraud, and a lack of control over personal data," Dr Philip Bos, a security expert and founder of privacy protection software company BlueKee, told 9news.com.au.

By sharing personal documents and other information with a single provider, the digital ID would – if implemented properly – negate the risk of identity theft from the likes of the data breaches and hacks that hit Optus, Medibank and Latitude in recent years.

"Australia is designing the system with a lot of security benefits," Perry says.

"So hopefully a benefit of the system is that we'll have less of those security breaches like Medicare and Optus because we're not sending those digital scans (of ID documents) via email to set up a bank account that kind of thing. 

READ MORE: What does the supermarket code of conduct actually do?

"So it'll actually stop that over-sharing of personal information… you won't be sharing that data in and of itself, you'll just be sharing a kind of tick of approval."

In addition to the practical, personal benefits of not having to replace licenses, passports and other documents after a hack, Mealy says the digital system can also provide benefits to small and medium-sized businesses that need to verify their customers' IDs.

"From a cybersecurity perspective, it reduces what we call the 'attack surface', that being the risk of our information getting out because the more organisations that have it, the more accessible it can be," she says.

"A lot of our small to medium enterprises, perhaps they don't have as advanced cybersecurity practices – often they cost a lot of money, they take up a lot of expertise. 

"So we're trying to protect those other organisations from attack as well."

Are there any concerns about the digital ID?

Before passing the Senate, the digital ID legislation was put before a committee, which heard a number of concerns from experts about the new laws.

Perry says most of those have since been addressed – although one remains.

"There were definitely concerns that we had and we appeared before the committee hearings and provided submissions around things like voluntariness, inclusion and accessibility redress mechanisms, and a lot of that has actually been taken on by the government and included as amendments, which is fantastic. 

"I think the one thing that isn't quite up to scratch that we were hoping for is the law enforcement and police access to information."

Under the laws, police will require a warrant to access any information stored as part of a digital ID, but Perry says the restrictions could be tighter.

"There are some protections in there. Police can't just access whatever they want," she says. 

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"But it's a lower threshold than we would have liked to have seen. So we would advocate that any law enforcement or police access needs to be highly restricted and for investigation of serious crimes only."

And while the system will mitigate the risks of data breaches from cyber attacks on all the organisations that would otherwise have stored copies of IDs, there is still the possibility of an attack on myGovID.

"It's susceptible to what we would call an 'adversary in the middle' or a 'man in the middle' attack," Mealy says.

"That means if someone can get between the app and the government servers, then that can cause problems. But this type of system is generally vulnerable to that kind of attack."

Overall though, the system is a step in the right direction, Perry says.

"It is actually a really decent piece of legislation," she says.

"There's good redress mechanisms that will be built into the legislation, destruction of information, that kind of thing. So on the whole, we're pretty happy with the way that they've amended it."

READ MORE: What's actually included in the government's DV announcement

Will the national digital ID be compulsory in Australia?

No.

While some of the concerns aired in Senate committee hearings did go to the voluntariness of the system, the digital ID, as currently legislated, will be completely voluntary.

When will the national digital identity be introduced?

While the legislation is yet to pass, myGovID is already up and running, although only for around 130 government services – you can't use it to identify yourself with private companies yet.

The legislation is expected to pass parliament in the coming weeks once the House of Representatives begins its next sitting session following the Federal Budget on May 14.

As for when private companies will get access to the system, that is due to happen within two years of the new laws coming into effect.

A major search is under way in South Australia for a convicted child rapist who is wanted for questioning in relation to a new alleged sex crime.

Police last night issued a statewide alert in the hunt for 44-year-old Allan Hopkins, who is wanted for alleged serious sexual offending involving a child.

He was earlier thought to have fled the state to Victoria, but Victoria Police told 9News they no longer believed he was there.

READ MORE: War crimes whistleblower begs leniency as prosecutors seek jail time

The search comes more than a decade after he was convicted of raping a child.

He pleaded guilty to abducting a 10-year-old girl sleeping in a home in Paralowie that he had been robbing in 2007.

He took her to a nearby school, where he raped her twice. 

Hopkins received the minimum sentence of 8½ years and was eligible for parole in 2017. It is unclear when he was released.

The older brother of the survivor said they were distraught to think Hopkins had allegedly harmed another child.

"She's real devastated as of today. She broke down, her heart was broken," he told 9News.

READ MORE: Childcare predators handed 63-year sentence for 'disturbing' abuse

Hopkins is described as Caucasian with short brown hair and brown eyes and is 185 centimetres tall with a solid build.

He has a skull tattoo on his upper right arm.

He is believed to be driving a grey 2022 Mazda BT50 ute with South Australian registration XC101T.

Anyone who spots him, his vehicle or has information on his whereabouts is urged to call police assistance on 131 444 immediately or triple zero in an emergency.

A 19-year-old man from Malaysia has been charged with trying to smuggle live native lizards out of Australia.

Australian Border Force and wildlife officers allegedly found geckos, spiders and scorpions at an address in the Perth suburb of Subiaco yesterday.

The wildlife, as well as three digital devices, were seized. 

READ MORE: Man and woman charged after seven puppies dumped by Adelaide road

The teenager was consequently arrested and charged with one count of attempted export of a regulated native specimen.

The investigation came after an air cargo company alerted authorities to three lizards found in a consignment labelled "toys" bound for Malaysia in February.

"The lizards were suspected to be destined for sale through the lucrative international wildlife market," the Australian Border Force alleged.

READ MORE: Accused mushroom killer Erin Patterson pleads not guilty

A public appeal for information led to several credible tip-offs, which Australian Border Force assistant commissioner Chris Waters said helped investigators make the arrest.

"This is an outstanding result, which quite possibly has prevented even more Australian wildlife being sent overseas for profit – a practice which is not only cruel but many of the animals smuggled this way sadly don't survive the journey," he said.

Anyone with information about the import and export of wildlife can contact Border Watch here or email the Department of Biodiversity, Conservation and Attractions on wi*****************@*********ov.au

A man with an axe in his bag has surrendered to police after an incident in the car park of the Crime and Corruption Commission headquarters building in Brisbane.

Police received a call about an armed 49-year-old man inside the CCC building on Saint Pauls Terrace in Fortitude Valley at around 4.20pm.

"At 5.45pm, the man was taken into custody by police who have subsequently located a small tomahawk in the man's bag," Queensland Police said in a statement.

READ MORE: Interest rates on hold despite borrowers desperate for relief

He is currently assisting police with inquiries.

It is unclear what his motive was.

No one was injured during the incident.

Gruesome details of the alleged torture and murder of a Queensland man have been heard when one of his accused killers faced court.

Sam Wilcox was allegedly found partially buried alive and unconscious with critical head injuries at a rural property at Mount Mee, in Moreton Bay last Wednesday.

The 23-year-old was rushed to the Royal Brisbane and Women's Hospital, where he died from his injuries on Friday night.

READ MORE: Interest rates on hold despite borrowers desperate for relief

Bella-Louise Scheibel, 21, and 23-year-old Cooper Bunney were charged with offences including murder, torture, common assault, deprivation of liberty, and grievous bodily harm.

Scheibel appeared in court via videolink today on a string of charges, including the serious assault of a police officer.

She was asked to submit a disease test after it was revealed she allegedly spat at the officer.

READ MORE: The winners and losers of this year's 'family-focused' Victorian budget

Court documents show Schiebel and her co-accused Bunney allegedly used fencing wire to strangle and restrain their victim while torturing him over a three day period.

It will be alleged they then used an illegal shotgun to shoot him.

Both Scheibel and Bunney will next appear in Caboolture Magistrates court in July.

Investigators in Mexico have returned to the scene where two Australian brothers and a US national were killed during a suspected "robbery gone wrong".

Three Mexican locals were arrested over the weekend after the bodies of Callum and Jake Robinson and friend Jack Carter Rhoad were discovered 10 metres down a well.

Authorities told 9News' Alison Piotrowski they had not ruled out the involvement of further suspects.

READ MORE: Girlfriend and friends share tributes to slain Aussie brothers

A convoy of 20 army vehicles pulled up to the campsite on Monday (Tuesday AEST) in Baja California where the three men were last seen on April 27.

Forensic investigators were seen combing a remote dirt track for evidence as Mexico's National Guard scoured the above cliffs.

Police said they were unable to rule out any additional suspects as they were still collecting evidence and the investigation was ongoing.

READ MORE: Mediterranean staple may lower your risk of death from dementia

Two of the arrested trio were caught with methamphetamines. One of them, a woman, had one of the victims' cellphones when she was caught. Prosecutors earlier said the two were being held pending drug charges but continued to be suspects in the killings.

A third man was arrested on charges of a crime equivalent to kidnapping, but that was before the bodies were found. It was unclear if he might face more charges.

The Attorney General Maria Elena Andrade Ramírez said it was believed the brothers and their friend had been killed during an opportunistic robbery attempt.

But the execution-style killings had locals asking whether there could be links to organised crime.

Jake and Callum's parents, Debra and Martin, travelled from Perth to Mexico to identify their bodies before crossing the border into the United States.

A GoFundMe page has been launched to cover travel and accommodation and funeral costs while an investigation is under way.

The fundraiser had already raised US$250,000 ($378,788) out of its $300,000 ($454,545) goal by Tuesday evening.

A vigil was held for the three men in Callum's adopted hometown of San Diego. 

"Cal Robinson was just bigger than life," friend Peter Green said.

"An absolute legend, a guy that lit up the room. He had his own gravitational pull."