Do you recognise this man?
Two men forced their victim into handing over his bank card and PIN.
The incident happened at around 3pm on Saturday, 18 January.
One of the men suspected of the offence has since been arrested, charged, and appeared in court.
Officers are in the process of identifying the second man.
They would like to speak to the person in the image and ask anyone who knows him to contact British Transport Police.
Witnesses can text 61016 or call 0800 40 50 40 and quote reference number 294 of 18/01/20.
Alternatively, call Crimestoppers anonymously on 0800 555 111.
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Tags: Newham, Stratford, Public Transport