A man allegedly made sexually inappropriate comments to a woman on board a train from Lincoln to Sleaford.
During the journey at around 1.40pm on November 20, a man sat near a woman and started talking with her. The unknown man then started making a number of sexually inappropriate comments to the woman while staring at her.
The suspect had short mousey hair and was wearing a blue jumper and a t-shirt, British Transport Police said.
British Transport Police are investigating the public order incident and released an appeal for information on Thursday, December 12.
Anyone who was on board the train and saw what happened, or knows someone matching the above description, should contact British Transport Police. British Transport Police can be contacted by sending a text to 61016 or by calling 0800 40 50 40 quoting reference 141 of 25/11/19.
It can also be reported through the independent charity Crimestoppers anonymously on 0800 555 111.