A female conductor has been indecently assaulted on a train journey from Londonderry to Belfast.
The incident happened on Saturday when the woman intervened after a group of male passengers became rowdy.
The woman was allegedly grabbed by one of the men and verbally abused. She was then grabbed by another man as the group left the train at Mossley West.
The conductor was said to be left extremely shaken and upset by the ordeal.
A PSNI spokesperson said: "It is appalling that a woman was subjected to such attacks while simply doing her job. We are investigating and would like to hear from witnesses."