British Transport Police Officers investigating two indecent exposure offences in Merseyside have released images in connection with the incidents.
At 2.55pm on 10 August, a man sat across from a young woman on a service travelling between Hamilton Square, Birkenhead, and Bache moved to sit directly opposite her and touched himself inappropriately.
On another occasion at 3.11pm on 1 October, a man was reported to be touching himself through his trouser pockets while travelling on a train between Southport and Moorfields in Liverpool city centre.
Officers believe the man in the images may have information that could help their investigation.
If you recognise him, or have any information, please contact BTP by texting 61016 or calling 0800 40 50 40 quoting reference 349 of 01/10/21.
Alternatively, you can contact Crimestoppers anonymously on 0800 555 111.