A man has allegedly bitten a woman and attacked other passengers on board a train at Melbourne's Hawthorn station.
Officers were called to the station about 3.50pm after receiving reports a man had assaulted a woman, aged in her 70s, and up to five others on board the train.
Other passengers rushed over to assist and held the offender at Hawthorn station until police arrived.
Police have taken a man in his 30s into custody.
The man was affected by drugs at the time of the alleged attack, police say.
The woman will be taken to hospital for assessment.
"They sounded really terrified... usually there's a bit of noise around end of school time, but not that kind of terrified screaming," witness Rebecca McNally told 9NEWS.
Police are also investigating reports of people pushed onto the train tracks.
https://twitter.com/sket49/status/783901545557397504
Trains on the Belgrave line were impacted by the police operation.
This is a breaking news story. More information will be added as it comes to hand.
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