Graphic content warning: Shocking video emerges of thugs brutally bashing young woman at Auckland train station

A shocking video has emerged online of a group of vicious young thugs kicking, punching and pulling a young woman to the ground at an Auckland train station.

Auckland Transport media spokesman Mark Hannan told 1 NEWS they were aware of the attack, which took place on Sunday.

The footage shows a mob of teenagers, mainly females, gathered around a train shelter in West Auckland's Ranui.

The video then moves on to a young woman, wearing a blue jumper with the number 15 written on the back, throwing punches at another young woman sitting in the shelter.

A young man slides into the video at this point and starts pulling finger signs and yelling "east coast".

Two more young women behind him start laying into the victim with brutal blows to the head.

You can hear one young woman yelling "yo, c-side" over and over again.

A mob of about four young women are now punching and kicking the victim.

She is pulled to the ground, where they continue to kick and beat her. Just briefly a security officer wearing a hi-vis jacket appears in the background, while the fight is happening.

Auckland Transport has handed its CCTV footage from the station over to the police.

When 1 NEWS asked why the Auckland Transport security officer didn't intervene, Mr Hannan said it wasn't their job to get involved as they were not law enforcement officers and didn't have the power to do so.

He said their security officer's job was to contact the police.

Police say they are aware of the video, which was posted online.

They are still making inquiries.