POLICE are appealing for information after a Braintree woman was sexually assaulted on a train.

Two friends – both aged 24 – were assaulted onboard an early morning Northern Line service on August 15.

The pair were asleep when the assault took place.

Detectives have released CCTV images of a man they want to speak to.

Detective Constable Andy Parkinson, of British Transport Police's sexual offences unit, said: “At approximately 6.45am, two women boarded a northbound Northern line train at Camden Town station.

"They sat next to one another and, shortly after the train departed, both fell asleep.

“A short time later, a man approached one of the women and sexually assaulted her as she slept; only stopping when her friend woke and intervened.

"At this point, he touched the second woman inappropriately before getting off the train at Finchley Central.”

The victims, from Braintree and Barnet, north London, immediately called police.

DC Parkinson added: “We need to speak to the man pictured as a matter of urgency, as we believe he will be of great assistance to the investigation. He may live or have connections in East Finchley.

"If you recognise him, or have any further information, please get in touch with BTP or Crimestoppers.

“This was understandably an incredibly frightening experience for the two women and something nobody should have to experience.

"I would like to assure the public we are doing all we can to catch the person responsible and bring them to justice through the courts.”

Anyone with information can contact British Transport Police on 0800 40 50 40, or text 61016, quoting reference T/B3 of 02/09/15 or call Crimestoppers anonymously on 0800 555 111.