A young woman was filmed begging for someone to help her as two other women brutally assaulted her on the Elizabeth Line.
Footage posted to social media shows the victim sitting next to a window while her attackers stand over her.
Someone can be heard asking “are you dumb” before the two women are seen punching the victim’s head.
She starts screaming “help me” as one woman starts pulling her by her hair and throws her to the ground.
They then kick her while she is on the floor and hit her head multiple times.
The man filming has gotten off the train by this point but pleads “girls leave her” as he tries to hold the doors open.
Another man on the train gets involved and tries to split the women up but the two attackers still try to kick their victim before she eventually manages to escape onto the platform.
She was taken to A&E to be treated for her injuries, the police said.
The incident is believed to have taken place at around 10pm on October 29.
British Transport Police said: “We are aware of this video and enquiries into the incident are ongoing.
“Anyone with information is asked to contact BTP quoting ref 687 of 29 October.'
“Officers responded following reports of an assault on board an Elizabeth Line service towards Paddington station at around 10:10pm on October 29.
“One woman attended A&E. Enquiries into the incident are ongoing.”