"I was just thought it was one idiot who was drunk or something like that, but then he came back with others," he said.



"I'm beyond shocked. I came to show my support and I didn't expect this to happen. There's no place for this in our society."



Several videos obtained by Fairfax Media and posted on YouTube appear to show most of the confrontation between three young men and the protesters.



One man in a navy blue top appears to be a key instigator in the videos. He struggles with a woman over her "Save The Palace" placard while two others are trying to get him to leave.



At least two protesters recall him yelling homophobic slurs.

In the video, one of the protesters is heard shouting into a microphone and loud speaker: "Now we've got a bit of homophobia. What else would you expect from scum like this? One of them has just made a homophobic slur against one of our crew."



The comments appear to provoke the man into rushing towards him, triggering a larger confrontation. At least five protesters can be seen trying to restrain one of the three men while his friends try to pull protesters off of him. Everyone then collapses into a doggie pile on the footpath.



The man in the navy top is then seen in another video being restrained as he tries pulling the microphone cord away from the group. "You're defaming me," he shouts at the protesters. "It's called defamation law." The struggle turns into a second doggie pile on the foot path, and later ends up on the street.



Afterwards, the protester who was addressing the group with the loudspeaker tells the man: "Seriously, you attacked me. That's assault."



The man replies: "Well, dare, I say, f---ing take me to court. I am protesting against anti-development f---heads."



Mr Davies said he's suspicious of who the man and his friends could be, considering how the protest was organised in less than three hours.



"It seemed very targeted. They knew what they were doing. They came to try cause trouble."



Another one of the protester, Ben Mathews, agreed: "I'm concerned that they weren't there by accident. They knew what they were doing."



He said he recorded the men on his phone to document how it wasn't the protesters who instigated the confrontation.

"The one who is the loudest in the video was getting in everyone's face," he said. "He was yelling lots of stuff about public housing and homeless people."



Police said officers were called to the Palace Theatre at 6.34pm on Thursday evening, but they are still trying to confirm reports that men involved in the alleged brawl were later detained.

Melbourne City Council is pursuing emergency heritage protection for the building. At just before 3pm on Friday the state government was yet to confirm that the interim measure would be granted.

It is understood council staff have been unable to enter the building today to survey suspected damage to the interior. A spokeswoman said the council was monitoring the site on Friday. "There is no evidence of any activity taking place [today], she said."