Police described the man who fled the scene of a double fatality in the Fens as a “key witness” and urged him to come forward.

Jade Green, 24, and Kayleigh Harrison, 29, died from injuries received when the Vauxhall Astra they were travelling in was involved in a collision with a Ford Transit at 7.10am on November 9 at Murrow.

A third person, a man in his 20s, remains in a critical but stable condition in Addenbrooke’s Hospital, Cambridge,

A fourth person is believed to have been in the vehicle, but left the scene. He is being treated as a witness and may have key information to assist with the investigation. He is described as white, in his 20s, with dark curly hair and a beard.

Detective Inspector Alan Page said: “I’d appeal directly to the man who left the scene to contact us as a matter of urgency.

“I would like to stress that he is being treated as a witness and we believe he may have vital information to help us piece together a picture of what happened last week.

He added: “This was a tragic incident where two women lost their lives and a man remains in a critical condition.

“In addition to the man seen leaving the scene we would like to hear from anyone who witnessed the collision or saw the vehicles prior to the collision.”

Anyone with information about the collision is asked to call the Road Policing Unit on 101 quoting incident 73 of 9 November, or Crimestoppers, anonymously, on 0800 555111.