Two men were hospitalised with serious facial injuries following an attack on board an Elizabeth Line train between Ilford and Forest Gate.
British Transport Police (BTP) have released images of two people they want to identify in connection with the alleged assaults, which left both victims requiring multiple surgeries on their jaws.
It was reported that three young men approached the victims and sat next to them on the train at 11.55pm on Monday, May 9.
One of the group placed his arm around one victim and demanded they both handed their phones over.
Police were told the group continuously asked for the phones and became more threatening as the victims refused, including standing over them and kicking their legs.
They briefly walked away while laughing then came back and demanded the phones again.
It is alleged one of the victims was assaulted when he stood up and attempted to intervene, before the group repeatedly punched and kicked both of them in the face while they were seated.
BTP says a 19-year-old man was arrested in connection with the incident.
Anyone who recognises the two men in the CCTV images or has other information is asked to contact BTP by texting 61016 or calling 0800 40 50 40, providing reference number 11 of 10/05/22.
Alternatively, call Crimestoppers anonymously on 0800 555 111.
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