At 8.05pm on 18 February, the victim boarded a train at Manchester Piccadilly. During his journey he had a verbal altercation with a boy who was speaking loudly on his mobile phone.
The victim then moved down the train to alight at Holmes Chapel. The boy followed him down the train and repeatedly punched him in the head.
The boy got off the train at Crewe and boarded a Cardiff-bound service.
As a result of the attack, the victim suffered a deep cut on his lip that required stitches, as well as bruising on his head and ear.
Anyone who recognises him is asked to contact BTP by texting 61016, or by calling 0800 40 50 40 quoting reference 170 of 20 February.
Alternatively, call Crimestoppers anonymously on 0800 555 111.
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