Two brothers have been charged over the "abhorrent" bashing of an off-duty senior police officer near a Melbourne train station.
Monday's arrests came after Transit and Public Safety Command Assistant Commissioner Chris O'Neill, 60, was left with injuries including bleeding on the brain.
The man responsible for safety on Victoria's public transport did not identify himself as a police officer when the verbal and physical argument began on the grounds of St Kevin's College in Toorak on Saturday evening.
Mr O'Neill was attending a private function before the brothers allegedly attacked him. They had earlier been thrown off the train at Heyington station, next to the school.
The pair, aged 18 and 20, are charged with offences including intentionally and recklessly causing serious injury after being arrested at Malvern East.
They have been remanded in custody to face the Melbourne Magistrates Court on Tuesday.
Mr O'Neill suffered two broken ribs, kidney damage, and severe cuts and bruises in the bashing and was released from hospital on Monday.
"He has been seen by a neurosurgeon as he has some bleeding on the brain but he will make a full recovery and will return to duty sooner rather than later," Assistant Commissioner Bob Hill earlier told reporters.
"This was a despicable act and this behaviour is abhorrent."
Mr Hill also said witness accounts of the alleged offenders before Mr O'Neill was attacked "suggest they were either alcohol or drug affected".
"They were certainly affected to the extent they were urinating and vomiting on the train."
Police Minister Lisa Neville said she had been in contact with Mr O'Neill after the "cowardly attack".
"It is completely unacceptable that anyone should be attacked or assaulted just for going about their day," she said.
Opposition leader Michael O'Brien said Mr O'Neill and Victorians deserved better, accusing the government of dropping the ball on safety on public transport.
"What does it say about Melbourne when the man who's in charge of safety on our public transport system isn't safe himself?," he told reporters.
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