A commuter at Tottenham Court Road Tube station was subject to a "disgraceful and extremely violent assault" during rush hour.
The victim had tapped in at Tottenham Court Road station and was walking down the escalator when a man behind him yelled "walk faster".
The victim moved to the right to allow the man to walk past but instead the man grabbed hold of the victims chest and pulled him down the escalator.
Both men tumbled down the escalator and the victim struck his head on the floor before being punched multiple times in the face by his assailant.
After pulling himself free, the victim composed himself and continued towards the Northern Line platform but his attacker was waiting for him in the tunnel and set upon him again, punching him multiple times in the head.
The attacker made his way towards the Northern Line, leaving his victim with bruising to his face and a black eye.
The attack happened shortly after 5pm on October 20 and British Transport Police on Tuesday (November 21) released a picture of a man who they believe has "essential information" about the incident.
Investigating officer DC Angela Gates, said: “This was a disgraceful and extremely violent assault. The victim did nothing to provoke the man, the violence he was then met with was completely unacceptable.
“I would like to speak with the man shown in the images we have released as I believe he has essential information which could help us investigate. If you know who is, then please get in touch as soon as possible.”
Any information can be passed to BTP by sending a text to 61016 or by calling 0800 40 50 40 quoting reference 376 of 20/10/17.
Alternatively, pass information anonymously to Crimestoppers on 0800 555 111.
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