Staff and family members have been accused of posing as patients at a regional Victorian hospital's health clinic during a visit by the state health minister.
Victoria's health department is investigating an allegation that 10 staff or relatives of staff presented to Colac Area Health's urgent care centre within half an hour on August 9.
Health Minister Mary-Anne Thomas visited the clinic that day to inspect heart monitoring equipment, funded by a $221,500 investment from taxpayers.
"There's never a dull moment in urgent care," she wrote on Instagram at the time.
"Thanks to the nursing team at Colac Area Health for showing me through your workplace today and for delivering the very best of care to your patients."
All 10 of the allegedly fake urgent care arrivals were recorded in the database before being cancelled without being discharged after the minister left, the Colac Herald reported.
Ms Thomas said she was aware of the allegation and stressed the health department was taking it very seriously.
"If these allegations prove to be true, this is a very significant breach of trust that has been perpetuated by some in the health service," she told reporters on Thursday.
"I certainly would take a very dim view of any employees or others who have been involved in this."
Ambulance Victoria is separately investigating the allegation, a spokesman for the paramedic service confirmed.
An anonymous whistleblower first made the allegation to the Victorian Public Sector Commission in late August, with the minister and her office notified of it.
It was then referred to the Independent Broad-based Anti-corruption Commission, which found it was not within its remit.
The claim then landed on the desk of the Victorian Ombudsman, before the integrity watchdog informed the health department it was not investigating further.
The health department subsequently launched an investigation and will report back to the minister on its outcome.
Ms Thomas could not recall how many patients she met with during the visit but ruled out her office being involved in an alleged set-up.
"I visit health services all the time," she said.
"I see what's happening on the ground."
Ms Thomas was adamant the allegation had "nothing whatsoever to do with my office".
"If anyone is suggesting that I would take great offence," she said.
"I do recall it was pretty busy at Colac that day but I had no reason to be suspicious about what I saw."
Opposition Leader John Pesutto called for a retired judge or body independent of government to take over the probe.
"Given the pattern of misrepresentation (and) cover-ups of the Allan Labor government over many years, I'm simply not prepared ... to take the Allan Labor government at its word," he said.
"Let's have a truly independent inquiry to find what happened here and whether it is happening elsewhere across our health system."
Colac Area Health covers about 30,000 people in the Corangamite, Colac Otway and Surf Coast Shires.
The chair of its board, Tim Greene, said the health service took all complaints and feedback seriously.
"We are aware of an anonymous complaint which is being appropriately actioned," he said in a brief statement.
