This confronting video was filmed on a Sydney train and it has sparked calls for more security on our rail network.
The woman who filmed the teenage girls brawling says she kept calling for help, but no-one came.
This chaos between a bunch of teenagers was recorded on a train between Lidcombe and Redfern.
The violence erupted when this teenager abused a young girl, her friends came to help and this was the ugly result.
"Get off each other."
A passenger tries to stop it.
But the violence continues and when the train stops at Redfern the teen was pinned on the platform and punched repeatedly.
Laughs can be heard clearly in the shocking footage and it ends with sickening kicks to the head.
The woman who filmed it all says she called for security but no one came.
Maria Bomediano told 7 News: "I was just concerned because there was younger kids that are under 18."
The commuter claims when she showed guards she was asked not to publicise it.
The claim was rejected by Sydney Trains, it says a guard was close by and police were called.
Howard Collins, CEO of Sydney Trains, said: "Any information provided to us we will pass on and do pass on to police."
The rail union says security must be increased on late night trains.
Alex Cassons, from the Rail Tram Bus Union, added: "The government has actually got to do more to stamp out that sort of anti social behaviour."