Detectives want to question this man after two alleged incidents of sexual assault on the train from Dartford to London. One happened on April 14 at around 5pm; the other in February on the same train, the 16:39 service.
Police say the 37-year-old victim in the latest incident was travelling in one of the front carriages, having boarded at Lewisham. When touched, she confronted the man and he walked off down the train, leaving at Welling. The earlier incident also saw him leave at Welling.
Anyone with information is asked to contact British Transport Police on 0800 40 50 40 or text 61016, quoting SSUB/B4 of 17/04/14. Information can also be passed to the independent charityCrimestoppers on 0800 555 111