A woman was repeatedly groped for ten minutes on a train as it travelled between Clapham Junction and Richmond.

The woman, in her 30s, was attacked between 5.28pm and 5.38pm on November 3.

Police believe her attacker stayed on the train after her stop, and later got off at Twickenham.

The man is described as Asian, around 5ft 10ins tall and of average build. He was believed to be in his 50s and was wearing a grey flat cap and grey jacket.

Investigating officer PC Mark Luker said: “This was a highly distressing experience for the victim and I want to commend her bravery in coming forward to tell us what happened.

“We are doing everything to locate this offender and so I would like to hear from anyone who might have been on the train at that time and saw something taking place.

“We would particularly like to speak to the man who comforted the victim at Richmond as we believe he may have information that could prove vital.”

Anyone with information is asked to contact British Transport Police on 0800 40 50 40 or text 61016, quoting 199 of 5/12.