British Transport Police (BTP) have released an image of a man they wish to trace in relation to an off-duty cop getting thumped in Finsbury Park station on December 3.

The special constable was punched in the face after he told a man to stop vandalising a Piccadilly Line train.

The officer was able to snap a picture of a suspect before he was attacked, which shows a bearded man with a tattoo on his neck holding a bottle of Cockburns whisky.

The day after the attack, a BTP spokesperson said: “Officers are investigating after a man was assaulted in Finsbury Park Underground station.

“At around 9.30pm, it believed the man, who was about to board a Piccadilly Line service, intervened after noticing some anti-social behaviour on the platform and was then assaulted.”

Anyone who witnessed the incident or recognises the suspect is asked to contact BTP by texting 61016 or calling 0800 40 50 40 and quoting reference 604 of 03/12/18.”