A woman was sexually assaulted on a train but none of the other passengers intervened because they thought the victim and her attacker were a couple, police say.
According to British Transport Police, a man followed the woman onto a train at London Bridge station at 12.53am on Friday 18 July.
He sat next to her and touched her inappropriately. This continued for around 20 minutes before he departed at Chislehurst in south east London.
There were a few people on the train at the time who may have thought the pair were a couple and were reluctant to step in.
This was not the case and I am urging these people to come forward as they may have information crucial to our investigation.
- Detective Constable Andy Parkinson
British Transport Police have released a picture of a man they would like to speak to in relation to the incident.
Anyone with information is asked to contact the British Transport Police on 0800 40 50 40, or text 61016, quoting reference B8/SSUB of 15/08/2014.