Pauline Peart, 25, of Waltham Abbey, died from a single gunshot wound after the shooting in Tottenham, north London, at about 2300 GMT on 10 March.

She had been sitting in her car with a friend in Hampden Road when three men walked past, and then apparently turned back.

One then pointed a handgun through the open window and fired once, hitting Ms Peart in the back.

Her friend then took her to a nearby house, where she died at about 2330 GMT.

Detectives say they are keeping an open mind about the motive, and about who the intended victim was.

The first of the CCTV pictures released on Friday shows three men walking together towards Tottenham High Road along Hampden Lane about 20 minutes before the murder.

A second picture shows two men returning 10 minutes later, while the third shows an elderly man and woman walking along the road in the same direction a few seconds afterwards.