Do you recognise this man?
A man - who was either drunk or under the influence of drugs - boarded a train at Wembley station at 10.10pm on Tuesday July 6, according to the British Transport Police (BTP).
During the journey, he approached a woman who was travelling alone, allegedly sexually assaulted her then got off the train at Solihull station in the West Midlands.
CCTV images have been released by officers investigating the alleged attack on board the train which was travelling from London to Birmingham Moor Street.
The BTP believes the man shown may have information which could help in their probe.
If you recognise him or have any information, contact BTP by texting 61016 or calling 0800 40 50 40.
Alternatively, call Crimestoppers anonymously on 0800 555 111.
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