British Transport Police have released a CCTV image of a man they are searching for following an incident on a train heading from Edinburgh to Airdrie earlier this year.
The male is described as having a "strong" Scouse accent and officers believe he could have information to assist them with their investigation.
The incident took place onboard an Edinburgh Waverley to Airdrie train service between 11.09pm and 11.30pm on Monday, January 17.