At 8.30pm on Wednesday 26 January, there was an altercation on the train between a man and a woman during which the woman was sexually assaulted.

One man has been arrested in connection.

Officers are keen to speak to anyone who witnessed the incident, or anyone with information to assist their enquiries.

Witnesses, or anyone with information, can contact BTP by texting 61016 or calling 0800 40 50 40 quoting reference 531 of 26/01/22.

Alternatively, you can call Crimestoppers anonymously on 0800 555 111.