A man was punched repeatedly by a fellow passenger following an argument on board an Overground train from Homerton to Stratford.
And now British Transport Police have released a picture of a man they wish to speak to in connection with the assault.
During the journey, which took place at around 8.30pm on Monday, August 19, two men began to have an "aggressive" argument.
The victim, who is in his 30s, was punched in his head and body a number of times, suffering cuts and bruises as well as a fractured cheek.
Police have this week issued a picture of a man they believe could help the investigation.
Anyone who recognises him is asked to call 0800 405040 quoting reference 625 of 19/08/2019, or Crimestoppers anonymously on 0800 555 111
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