A woman was spat and and threatened with being stabbed as she travelled on a train between Stratford and Upminster.
She was on board the c2c train with two friends when a man began shouting at them.
He then spat, missing the victim, and then threatened to stab the group.
Police have launched an investigation into the incident, which happened at around 9.50am on Saturday, July 25.
They believe that the man pictured may have information which could help them.
Anyone who recognises him is asked to contact BTP by texting 61016 or callng 0800 40 50 40, quoting reference 377 of 27/07/20. Alternatively, contact Crimestoppers anonymously on 0800 555 111.
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