The father of a man placed in a medically-induced coma after he was allegedly kicked in the head by police is demanding the officer lose his job.
An internal police investigation has been launched after dramatic footage of Sunday's arrest in Epping, north of Melbourne, was posted online.
In the vision, an officer appears to kick down on the prone man's head before a group of police pin him down.
"Am I witnessing this? What the f***," a witness yells out his car window.
"You've got his head."
Other angles of the arrest show a police car ramming the man before he runs away and trades blows with an officer.
After being subdued with pepper spray, an officer appears to repeatedly kick the suspect on the ground.
Police say the 32-year-old man, of no fixed address, became aggressive and damaged a police vehicle as he attempted to avoid arrest.
He was later taken to hospital where his father Glenn Atkins says he was put into a coma while undergoing a head scan.
"He was stomped on or kicked by the police," he told 3AW on Monday.
"The police had no right to do what they did."
Mr Atkins said his son suffers from bipolar and had been seeking treatment at Northern Hospital Epping.
He ran outside to meet a work colleague which prompted hospital staff to call the police, the father added.
Mr Atkins is calling on Victoria Police to sack the officer who allegedly kicked his son.
"It's disgusting," he said.
"This bloke needs to be accountable. He needs to lose his job.
"Policemen like that should not be in the job."
Professional Standards Command will review the arrest.
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