Aussies have slammed bystanders for not helping a passenger as he was attacked by a large group of teenagers on a Sydney train. 

The pack are understood to have been drinking and blasting music when a passenger asked them to turn their speaker down at 11.55pm on Saturday.

A bystander captured the ensuing fight as it erupted on the top half of the carriage.

The passenger put one of the teenagers into a headlock, before the rest of the group began pelting him with punches.

‘Leave him alone,’ one of the teenagers screamed.

‘Get out,’ another teenager demanded.

The passenger was pulled down the stairs by the group while taking blows to the back of the head.

Terrified bystanders watched on, frozen in their seats.

The pack are understood to have been drinking and blasting music when a passenger asked them to turn their speaker down at 11.55pm on Saturday

A woman could be heard off-camera frantically telling someone to call the police and push the button on the train for security.

The group is understood to have fled after the train arrived at Strathfield Station, in the Inner West, before police arrived.

The passenger remained on the train.

Footage of the disturbing brawl was shared to social media, where Aussies slammed the teenagers.

‘Australia has a problem with teenagers. They have no law and do what they want, and you can’t do or say anything,’ one wrote.

‘They act like this because they are untouchable. This government is too weak to do anything with them,’ another added.

Others took issue with the fact that none of the bystanders appeared to intervene.

‘The way nobody does anything makes me sick,’ one wrote.

The passenger put one of the teenagers into a headlock, before the rest of the group began pelting him with punches

‘Glad to see the grown men helping out,’ a second said sarcastically. 

The passenger later clarified on social media that he had asked the teenagers to turn down the speaker as he could hear the music through his headphones.

‘Their leader (the one I’m holding down) kept charging after to start a fight,’ he wrote.

‘He was the only one punchable. They got me down eventually and kicked the s*** out of me.

‘I didn’t see the whole clan before talking to them. I should have just changed carriage and let the yungunz have their little fun night.’

A NSW Police spokesman told Daily Mail that officers were aware of footage showing the brawl occur between Redfern and Strathfield stations. 

‘Anyone with information about this incident is urged to contact Parramatta Police Transport Command on 02 9688 8436 or Crime Stoppers on 1800 333 000,’ he said.

Daily Mail contacted Transport for NSW for comment.