Detectives have released an image of a man they wish to speak to following a sexual assault at London Bridge Underground Station.
The incident happened on Thursday 27 November at about 9.30pm.
The victim, a 27-year-old woman, passed the ticket barrier making her way to the escalators which lead to the Jubilee line platforms.
As she made her way through the station she was sexually assaulted.
Detective constable Suleman Yazdani said: "This was a very serious assault, which has left the victim extremely shaken.
"I am very keen to identify the man in the CCTV image as he may prove vital in our investigations. I would also like to appeal to members of the public who may have been in the area and may have witnessed the incident to come forward."
Anyone with information is asked to contact British Transport Police on 0800 40 50 40, or text 61016, quoting reference TSUB/B8 of 15/12/14. Information can also be passed anonymously to independent charity Crimestoppers on 0800 555 111.