Detectives investigating four sexual assaults Dollis Hill and Neasden have issued CCTV images of a man they wish to speak to.
Three women reported being assaulted on March 6 between 7.30pm and 11.45pm in the Dollis HIll and Neasden vicinity.
In each case they were walking alone when they were approached from behind and sexually assaulted, Scotland Yard said,
A fourth attack was reported in the same area on March 24 at about 1am.
Anyone who recognises the man, aged between 25 to 35, is asked to come forward.
Officers believe he is of Asian or Mediterranean appearance, of medium build and was wearing a dark coloured bomber jacket, dark trousers and shoes and a black hat at the time of the attacks.
Det Serg Steve Sussex, said: "While we are keeping an open mind as to whether these assaults are linked, we are extremely keen to speak to the man identified in these images.
"We would encourage women to be vigilant when walking home in the evenings and where possible to stick to well-lit areas.
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