A wheelchair-bound protester says police left him convulsing on the ground and offered no assistance after coming from behind to spray him with capsicum foam.
Oliver Butterfield is denying police claims that he was a danger to himself when they fired capsicum foam at him while he tried to fasten himself to a gate at an immigration detention facility in Melbourne on Saturday.
Mr Butterfield, aged 25, has spina bifida and only limited use of his legs.
Video footage shows Mr Butterfield sprayed twice from behind by police while he tried to fasten himself to the fence, and again directly in the face while he lay thrashing about on his back on the ground after removing the lock.
He told AAP that police appeared to be trying to punish him because he was protesting.
Police said in a statement they acted because they were concerned for Mr Butterfield's safety, and he was later provided with aftercare and suffered only temporary discomfort.
"Victoria Police's primary concern is that of the safety of members of the public and make no apology for the tactics used in the circumstances," police said.
Mr Butterfield denied the police claims and said the foam was used at point blank range while he convulsed on the ground.
"The police provided no aftercare. It was only my friends that provided any aftercare.
"They had to pull my eyelids open to pour water, and then they made me snort water because I was vomiting from the pepper spray down my throat," he said.
Since the incident he had been "in a bad way" although he should eventually be fine, he said.
Mr Butterfield, a full-time hip-hop musician, said for a few months he had been conducting music workshops with people inside the Melbourne Immigration Transit Accommodation Centre.
He was protesting against the detention of children in immigration facilities.
Mr Butterfield has sought legal advice since the protest and said while he did not want monetary compensation, he did want police to be held to account for their actions.
Asylum Seeker Resource Centre spokeswoman Pamela Curr distanced herself from the protest and said it was possible Mr Butterfield could have been a danger to himself by locking himself to the gate.
"Other people there were telling me that Socialist Alternative and anarchists were rocking that gate trying to knock it over ... if this guy had been attached to the gate and that gate had gone over, he could have hung himself," she said
Police punitive, wheelchair protester says