Stories about people travelling in buses from cities and descending on small towns and stripping the supermarket shelves are rife on social media – and some mainstream media – but the evidence is scarce.

Guardian Australia, along with several ABC and regional journalists, have attempted to back up the claims about the organised bus tours of shoppers but all came up empty.

So @calebcluff has done a national service and gone @snopes on the whole "busloads of Melburnians" coming to regional towns to take our groceries rumour. https://t.co/TCPUvJkPK1 — Eliza Berlage (@verbaliza) March 19, 2020

Facebook feeds are full of stories about someone’s sister who saw a minibus pull up outside a grocer in Deniliquin, or Kyneton, or Gulgong, but no one has a photo to prove it.

In the age of camera phones, we couldn’t find any credible photographs of this reported phenomenon anywhere.

Guardian Australia found one supermarket where a security guard had been employed to check shoppers were not from out of town, but no evidence of buses.

Some of the posts say the buses are full of “Asian” or “Chinese” passengers.

“Every report I’ve seen said those on the buses were Chinese,” said one commenter. “Highly organised with different buses hitting different towns at the same time.”

The Daily Mail called it “tourist panic-shopping” and quoted “angry residents” on Facebook: “People from Sydney [are] packing cars to the brims. Our supermarkets don’t get enough supplies, only enough for our population let alone hoarders. It’s really sad and I think it needs to be policed from now.”

On Tuesday the claims were given credibility by a story in the Age headlined “Busloads of city dwellers stripping regional shelves bare”, although there was no racial element in the report.

“Regional towns are being swamped by busloads of panicked ‘Coles tourists’ who are driving from the city to strip supermarket shelves of basic supplies,” the report said.

“The Age has heard reports of city-dwellers rushing supermarkets in Gisborne, Kyneton, Romsey, Seymour, Woodend, Daylesford and even in towns as far away as Kerang and Deniliquin.”

While the paper said they’d “heard reports” there was little in the way of evidence to back it up and no photographic proof.

Guardian Australia contacted two of the supermarkets mentioned in the Age – the Romsey IGA and the Woodend Coles – and both stores denied busloads of people from other areas were shopping.

On Thursday an appearance by home affairs minister Peter Dutton on the Ray Hadley mornings show on 2GB gave the story a boost – and fuelled its racial overtones.

Hadley claimed he was “sceptical at first” but now he had “photographic evidence” that hoarding and panic buying had morphed into busloads of Asian shoppers descending on small towns.

“It’s a busload of Asian Australians, I presume with a trailer on the back, just going to these shopping centres and shops … Aldi, Coles and Woolies and clearing the joint out,” Hadley said.

Dutton agreed and said there was an investigation under way into what he believed was a criminal enterprise.

“We do have some people I think that are profiteering, Dutton said.

“They’re hoarding, not for their own consumption, I think they’re either sending some of the products overseas or they’re selling it in a black market arrangement in Australia.

“I’m gonna come after those people … It won’t be a pretty experience when we deal with them.”

Each shop owner I've spoken to so far says there are no busloads in their town - but that they've heard of it happening in (insert nearby town). Then I call that town - and it's not. Feels very much like an urban legend. Happy to be proven wrong, though. — Eliza Goetze (@elizagoetze) March 20, 2020

The radio station posted grainy photographs on its website and on Facebook, which a listener called Ben claims to have taken “in front of a Woolworths and says the bus went to Orange, Parkes and Forbes in the one day”.

Guardian Australia spoke to Coles management who said they knew nothing about it.

Exactly. I called every supermarket and the bus company for that story and not a single person could say it was happening. Get on social media and it’s an epidemic that’s destroying our country. — Ben Palmer (@palmersaurusrex) March 20, 2020

One of the people quoted by the Age, Reverend Mel Clark from St Mary’s Anglican church in Woodend, a tourist destination 30 minutes’ drive from Daylesford in Victoria, was the only person we found who had witnessed buses at their supermarket. Clark told Guardian Australia she had seen two minibuses of about 15 people pull up outside Coles last week.

The same in Dubbo, Mudgee etc. People are irate about buses coming into their towns from the city to take their supplies. In investigating, all we've heard are denials. I also have seen a single photo as evidence https://t.co/PPMQSG64lu — Lucy Thackray (@LucyThack) March 20, 2020