A sex offender who lured a child to Northolt Station and assaulted her on board a train has been jailed for four years and forbidden from using the internet for eight years.

Deneil Walker, 21, groomed a girl on Snapchat into meeting him in West London on October 4, where he paid for her travel and took her on a train to Liverpool Street.

On the journey, Walker claimed he was too nervous to go to the loo alone and lured her into the toilets where he sexually assaulted her, then left, abandoning her on board.

The distraught victim approached members of the public for help and she was soon taken to the nearest police station.

Within hours, police were knocking on the Hertfordshire local's door and finding crucial evidence such as the victim's train ticket inside his bag.

At court he pleaded guilty to two counts of engaging in penetrative sexual activity.

He was also signed onto the sex offenders register and handed a restrictive sexual harm prevention order.

Among the restrictions he was banned from using a phone, or any device that connects to the internet, for eight years.

Detective Constable Vicki Bladen said: "The victim was in touch with us straightaway, a very brave thing to do while dealing with such a distressing offence.

"Within hours we were knocking on Walker's door, finding crucial evidence such as the victim's train ticket inside his man bag. He was arrested, charged and put before the courts.

"Sexual crimes are a priority for British Transport Police. Every person has the right to travel in safety, and anyone who is a witness or is a victim to a sexual crime is strongly encouraged to contact us.

"No report is too small or trivial, we will always take you seriously. Contact BTP by texting 61016 or calling 0800 40 50 40."