Gay rights activists will rally in Sydney this week to demand an external investigation, apologies and compensation for alleged police brutality at last weekend's Mardi Gras celebrations.
Politicians and community groups called for an inquiry after a video emerged that appears to show a handcuffed 18-year-old, Jamie Jackson, being thrown to the ground by an officer at the festival about 11.30pm (AEDT) on Saturday.
Bryn Hutchinson, 32, later came forward to say he had been thrown to the ground by several officers in Darlinghurst after a disagreement over whether he should be allowed to cross a road.
"I was pushed onto the ground, kneeled on and kicked several times," Mr Hutchinson told AAP on Wednesday.
It is understood both men have been charged with assaulting police.
NSW police have confirmed two internal investigations are being carried out and urged the community not to jump to conclusions about the arrests.
"While two incidents is still two too many, in the grand scheme of things we don't have a super big problem," NSW Assistant Police Commissioner Mark Murdoch told reporters.
NSW Premier Barry O'Farrell said he was confident a police investigation would "get to the bottom of what went on", and Police Minister Mike Gallacher said oversight from the ombudsman meant no additional investigation was necessary.
NSW Police Association president Scott Weber, a serving officer, said an internal investigation was appropriate as NSW police were subject to more oversight than any other force.
In the video of Mr Jackson, an officer is seen to throw the handcuffed man to the ground before standing with one foot on his back for at least 20 seconds.
The initial encounter between the young man and officers was not shown.
Mr Jackson said on Wednesday it was a "completely excessive use of force" and one of the police officers present had apologised to him.
"One of them was like, 'I'm actually so sorry,'" he told the Seven Network.
Mr Murdoch said the video showed only part of a larger incident and the full circumstances would be revealed later.
Activists aligned with the Community Action Against Homophobia (CAAH) group plan to march from Taylor Square on Oxford Street to Surry Hills Police Station on Friday, and say 1200 people have already said they will attend.
CAAH member Karl Hand told reporters he had met with Mr Hutchinson on Sunday morning, and the man's wrists were swollen and marked by deep handcuff grooves.
"He couldn't use his knife and fork. I had to cut up his food," Mr Hand said.
"Every Mardi Gras we talk to people who have been brutalised by police. It's been happening since 1978," he said.
His group wants the two men to receive apologies and compensation from police.
Human rights lawyer-turned-researcher Dale Mills said oversight by the ombudsman was not enough.
"In my opinion, the ombudsman's office is part of the problem. They don't have the legislative power, or the resources, or the political will," he said.
"Really what's needed is a separate statutory body that can investigate allegations of police misbehaviour."