Do you recognise this man?
Officers would like to speak him in connection with an assault on a Central Line Tube train from Bank to Liverpool Street on 26 June.
At approximately 9.55pm, a man boarded at Bank station and started to verbally abuse a passenger before physically assaulting and threatening him.
The victim, who was visibly shaken, then left the train at Liverpool Street station.
Officers would like to speak to the man in the CCTV image because they believe he may some information which could help the investigation.
If he looks familiar or you have any information which could help the investigation, please call 0800 40 50 40 or text 61016, quoting 339 of 6 August. Alternatively, you can ring Crimestoppers anonymously on 0800 555 111.