A woman was killed and three people left injured in a car crash following a police pursuit on the M25.
The crash – involving three cars – happened in Parklands in Waltham Abbey, Essex, at about 22:00 GMT on Thursday.
Essex Police said officers had been trying to stop one of the vehicles.
The woman died at the scene, although it is not known if she was in the car being pursued. The crash has been referred to the Independent Office for Police Conduct.
Essex Police said officers from the Bedfordshire, Cambridgeshire and Hertfordshire road policing unit had been trying to stop the car on the motorway.
The scene of the collision will remain closed for some time, the force added.
A spokeswoman for the East of England Ambulance Service said three people were taken to Princess Alexandra Hospital in Harlow for further treatment.
Essex Police has asked for witnesses and drivers with dashcam footage to contact them.