Police are hunting a train pervert who sexually assaulted a teenage girl on a journey through east London.
A man approached her and then started to touch the teenager through her clothing.
She protested and ran off the train when it reached Hackney Wick.
British Transport Police now want to speak to anyone who may have seen the October 13 attack, which took place at around 6pm.
They also want to speak to people who may have seen the man acting suspiciously before the sex assault.