A man was kicked and subjected to homophobic abuse on board a Jubilee line train to Stratford.
After he boarded the service at Westminster, he heard a man making racist comments.
That man then turned his attention to the victim and started making homophobic comments about him.
The victim tried to film the incident but his phone was grabbed by the man making the comments, who also kicked him as he got off the train at Stratford.
Police investigating the incident, which took place at around 9.15pm on Wednesday, September 12, have now released a picture of a man they believe has information about what happened.
Anyone who recognises him or who witnessed the incident is asked to call British Transport Police on 0800 405040, or text on 61016, quoting 151 of 10/10/18.
Alternatively, call Crimestoppers anonymously on 0800 555 111.
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