Victoria's ombudsman has described the treatment of a V/Line passenger as heavy-handed after he was thrown to the ground and held there for nine minutes for drinking on a train.

The 62-year-old man was travelling from Castlemaine to Melbourne last March when he was detained at the Sunbury railway station.

Security footage shows the V/Line authorised officers escorting the man off the train with his pants around his ankles before forcibly restraining him on the ground.

The ombudsman has ruled the officers used unnecessary force and has recommended that their training be reviewed.

Authorised officers are employed by public transport operators to check tickets, prevent anti-social behaviour and are allowed to arrest a person who is alleged to have committed an offence under the Transport Act.

Transport Minister Terry Mulder has accepted the ombudsman's recommendations.

"If we can do anything to improve that training we'll do so," he said.

"If anyone is conducting their work as an authorised officer in an inappropriate manner then that has to be fully investigated and that issue has to be dealt with."

The ombudsman has also recommended that security cameras be installed on all V/Line trains.

Mr Mulder says cameras are already being trialled on one three-carriage train.

"I'd like to see the results of that particular trial," he said.

"We want to make sure when we go down that pathway we get the best possible and most modern technology that is available."

V/Line has apologised to the man involved.