A 15-year-old girl was sexually assaulted on a bus.

On May 18 at around 8am, a 15-year-old girl was assaulted on the 236 bus heading towards Barnet.

The suspect was already on the bus when the victim boarded, standing by the back doors of the bus.

He sexually assaulted her repeatedly, even after she moved away from him.

Investigating officer DC Joanne O'Connor, from the Met's Roads and Transport Command, said: "This incident has left a young girl feeling unsafe getting on a bus to and from school.

"There is a need to catch the person responsible as soon as possible as his behaviour causes great concern.

"I would urge anyone with any information on who the suspect may be, or anyone with information about the incident, to come forward and help with our investigations."

The victim intended to get off the bus but the suspect suddenly alighted at Gravel Hill.

He is described as a white man, with brown hair, in his 20s or 30s.

There have been no arrests at present.

Any witnesses or anyone with information is asked to contact DC O'Connor on 07500 607 652, or to contact Crimestoppers anonymously on 0800 555 111.