Victoria’s health department is investigating an allegation that 10 staff or relatives of staff presented to Colac Area Health’s urgent care department within half an hour on August 9.

Health Minister Mary-Anne Thomas visited the hospital in the state’s southwest that day and later commended the hospital’s nurses in a post on social media.

“There’s never a dull moment in urgent care,” she wrote on Instagram at the time.

All 10 of the allegedly fake urgent care arrivals were recorded in the system before being cancelled without being discharged after the minister left, the Colac Herald reported.

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.”

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 allegation 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 and on its outcome.

Thomas could not recall how many patients she met with during the visit but ruled out her office being involved in the alleged set-up.

“I visit health services all the time,” she said.

“I see what’s happening on the ground.”

Thomas said 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.”

Colac Area Health, which covers about 30,000 people in the Corangamite, Colac Otway and Surf Coast Shires, has been contacted for comment.

– AAP