A teenage girl was left "scared and upset" after a man performed a sex act in front of her on a train.

Police have issued a photo of a man they want to question after the incident, which happened on a Dartford to Cannon Street train.

The suspect is said to have approached the 16-year-old girl and started performing an indecent act while staring at her.

Detective Constable Andy Parkinson said: "A man who boarded at Dartford sat opposite the girl, and began to touch himself inappropriately while staring at her.

"He left the train at Abbey Wood. The girl stayed on board, but was left scared and upset by what happened."

It is said to have happened shortly after 4pm on Friday, September 19, but detectives believe the same man committed a similar offence on Wednesday, May 14.

DC Parkinson added: "We issued a media appeal for information regarding the May incident in July, but, while we received several calls from the public, the information received did not lead to the suspect being identified.

"I believe the man in the image I am issuing today has information about both incidents.

"Do you know who he is? Please contact us. We take all incidents of unwanted sexual behaviour on the rail network extremely seriously and need to find the man responsible."

Anyone with information is asked to call British Transport Police on 0800 40 50 40, text 61016, quoting reference SSUB/B4 of 06/10/2014 or call Crimestoppers anonymously on 0800 555 111.

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