Police have made a breakthrough in rape investigation using DNA and CCTV footage.
Following a review of forensics and the original investigation detectives pieced together a full DNA profile of the suspect.
Detectives from the Homicide and Major Crime Command are appealing for the public's help to identify a man suspected of a rape in Yiewsley, Hillingdon in 2013.
At around 2.30am a 27-year-old woman was walking home.
She was attacked and raped in an alleyway that runs onto Fairfield Road, near to the junction with the High Street in Yiewsley.
The suspect is described a white man of stocky build.
Detectives released CCTV footage of a man leaving the alleyway who they wish to speak to in connection with the rape.
He was wearing a dark jacket, light coloured top and dark trousers.
He left the alleyway, turned into Fairfield Road and into the High Street. anw walked south along the road in the direction of West Drayton.
About a minute later a car drives along the High Street, travelling in the same direction that the suspect was seen to walk.
The attack took place on June 16, 2013.
Information to incident room on 020 8358 0200 or Crimestoppers, anonymously on 0800 555 111.