“Fuming and ready to go,” she wrote, “we are so sorry the show is cancelled due to the event not organising proper security.

“The barriers being broken in has made them deem it unsafe to play.”

Amyl and the Sniffers performing as the support act for AC/DC at the MCG on Wednesday night.

Amyl and the Sniffers performing as the support act for AC/DC at the MCG on Wednesday night.Credit: The Age

Police said they were called to the square after reports of people “attempting to gain access to an event before it was cancelled”.

“No offences were detected,” a spokesperson said.

The support act, Public Figures, played for 40 minutes before officials stepped on stage to announce the cancellation.

Following the announcement, the tens of thousands of fans quickly dispersed. As of 9.30pm, only a dozen people were left in the square.

Amyl fans Meg Hill and Lyra Philp travelled from Apollo Bay for the gig and said they were disappointed that event staff didn’t anticipate the size of the crowd.

“I think people were pushing down the barriers, but they should have anticipated that,” Philp said.

“It’s a free event, a huge band, what are they thinking?”

Isabel Cook, also from Apollo Bay, said she spent all of her spare money on travelling to the gig to see her favourite band play for the first time.

Disappointed fans (from left) Isabel Cook, Lyra Philp and Meg Hill at Federation Square on Friday night.

Disappointed fans (from left) Isabel Cook, Lyra Philp and Meg Hill at Federation Square on Friday night.Credit: Karl Quinn

“They’re one of my favourite artists and I’ve wanted to see them for ages. I was so excited, I thought it was a joke when it came on the screen,” Cook said.

The concert, presented by Federation Square, the City of Melbourne and Double J, was advertised as a free gig offering “exclusive” tour merchandise for those who missed out at the AC/DC concert.

Get alerts on breaking news as it happens. Sign up for our Breaking News Alert.