A man was grabbed by the throat in a racist assault on board a train between Sheffield and Hull.
Police today (Tuesday, April 25) launched a CCTV appeal as they attempt to track down the man responsible for the 'awful attack'.
Officers want to speak to the man pictured, who they believe holds information which could prove key to their investigation.
The victim boarded the train at Sheffield on April 6, at around 5.51pm, and as he did so another man barged into him and racially abused him.
When he asked the man to repeat himself, he was grabbed by the throat and his neck was squeezed tightly, locking his arm out.
The attacker then pushed his victim backwards down the train, sending him crashing into another passenger.
The assailant remained on the train after the victim had got off.
PC Stephen O'Callaghan, from British Transport Police (BTP), said: "This was an awful attack on a man who was simply going about his journey. To be racially abused verbally or physically will never be tolerated.
"I am keen to speak to the man in the image who I believe holds information that could be key to our investigation.
"I am also keen to speak to anyone who was travelling on the service and who witnessed the incident. Everyone has the right to travel on the rail network without fear of crime of intimidation."
Anyone with information is asked to call BTP on 0800 40 50 40 or text 61016 citing the reference number 320 25/04/2017.
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