A teenager dressed as a penguin and his father were punched and kicked on a train by a gang of around six men after they asked if he supported Tottenham Hotspur.
The 19-year-old was waiting outside the train toilet, wearing a fancy dress penguin costume, when one of a group of around six men sitting nearby asked him if he supported the London football outfit. The teenager then used the toilet but, when he came out, found the men blocking his route back to his seat and being aggressive towards him.
The victim's 56-year-old father approached and tried to pull his son away, but both of them were then repeatedly punched and kicked by the group of men, British Transport Police (BTP) said.
The incident happened between 11.50pm and 12.25am on 21 December on the train from Liverpool Street in London to Chelmsford in Essex. The disorder spilled onto the platform at Chelmsford as the train arrived.
Both of the victims sustained injuries, including multiple cuts and bruises to their faces and bodies. Another member of the public who tried to help was also assaulted, receiving a black eye.
BTP officers would like to speak to the three men pictured in the CCTV images above in connection with what they called the "assault and affray", as they may be able to help with the investigation.
If you recognise them, or have any other information which could help, call BTP on 0800 40 50 40 or text 61016 with the reference number 228 of 9 January 2018.