Two women were sexually assaulted on buses and police have released the image of a man they want to trace.
The first victim, a 17-year-old girl, boarded a 316 bus in Cricklewood at around 4.40pm on August 1.
A man go on the bus around 15 minutes later and sat next to her, opened up a newspaper on his lap and sexually assaulted her.
The victim confronted him and moved to a different seat, and the police believe he got off the bus in the Notting Hill Gate area.
The second assault took place on August 28 in the West End, where a woman in her 40s boarded a 36 bus and a man sexually assaulted her under similar circumstances, but this time the assault was prolonged.
PC Sarah Bunting, said: "These two victims were subjected to a sustained sexual assault, and their vulnerability taken advantage of in a public setting. They have both been left shaken and distressed by what's happened to them.
"We believe that the same man is responsible for both attacks, and we need the public's help to trace him. If you recognise the man in the CCTV still images, we would urge you to get in touch right away."
The man is described as white, in his 40s or 50s, of medium build and around 6ft tall.
On both occasions he was wearing a black baseball cape with a white logo, a black t-shirt, dark trousers and boots.
If you have any information call the Roads and Transport Command on 101 call Crimestoppers anonymously on 0800 555 111.
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