A woman was sexually assaulted as she slept on a late night Southend bound train.
British Transport Police have released a picture of a man they need to speak to in connection with the assault, which took place between Prittlewell and Southend, in the early hours of this morning.
The victim, a 23-year-old woman, boarded the 12.50am service from Liverpool Street to Southend Victoria.
She fell asleep but was awoken by a man, who boarded at Prittlewell, sexually assaulting her.
Both the victim and her attacker left the train at Southend Victoria station, and the man left the scene.
DC Cudby added: “We have analysed onboard CCTV footage of the incident and are keen to speak to the man in the picture.
“I am confident he has key information on this assault.
“This was an extremely frightening experience for the victim and we need to find the person responsible for this assault as soon as possible.”
Anyone with information is asked to contact British Transport Police on 0800 40 50 40, or text 61016, quoting reference ESUB/B12 of 25/07/2014. Information can also be passed anonymously to the independent charity Crimestoppers on 0800 555 111.