Woman sexually assaulted on train between Dumbarton and Balloch
Police say it was witnessed by another passenger, but the victim hasn't come forward
A woman was sexually assaulted on a train in West Dunbartonshire.
While travelling between Dumbarton Central and Balloch at around 8.25pm, a man was blocking the aisle by standing between two seats.
The woman tried to get passed but he then touched her inappropriately, causing her to stumble back, before he left the carriage.
Investigating officer PC Marc Higgins said: "This was an assault witnessed by another passenger on the train, who reported this to police.
"The victim herself, who asked other passengers if they'd seen what happened, has not reported the offence to us - but that does not mean we'll stop investigating.
"We're committed to ensuring the railway is a safe place to travel for everyone and so if you were on the train and saw what happened, or if you are the woman who was assaulted in this manner, then please get in touch.''
The offender was a white man in his early 30s, with short dark hair.
He was wearing a black jacket, brown top and grey trousers.
The incident happened at around 8.25pm on September 23.
Those with information have been urged to contact British Transport Police on 0800 40 50 40 or text 61016 with reference 1700066980.