Transport for London (TfL) says it is working closely with police to identify the people responsible for the attack of a passenger at Osterley Tube station .
British Transport Police (BTP) appealed for information following the attempted robbery and common assault at the Piccadilly line station on November 20.
TfL has described the incident as “appalling”.
The incident occurred at 2.55pm when the 21-year-old man was attacked by a group of men who had been travelling on the same train, BTP said.
He was punched in the face and pulled to the floor, before the offenders demanded his phone and threatened to stab him.
At this point a member of staff at the London Underground station intervened and was also pushed.
The member of staff told the offenders to leave the station and then took the victim to the booking office before the offenders eventually left the scene, according to BTP.
CCTV images of three individuals who may have information which could help the investigation have been released by BTP.
Steve Burton, director of enforcement at TfL , said: “The violent attack on a customer and member of staff at Osterley station was appalling.
“Everyone has the right to go about their day without fear or intimidation and we do not tolerate any form of verbal or physical assault on our customers or staff.
“We are working closely with British Transport Police to bring the perpetrators to justice.”
No arrests have been made.
Anyone with information about the incident can call BTP on 0800 40 50 40 or text 61016, quoting reference 314 of November 20.
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