Police investigating a serious road crash at Aveley have appealed for witnesses and for information about a vehicle that failed to stop at the scene.
Officers were called to Sandy Lane, outside the Aveley landfill site, at about 2.40pm on Friday, February 8 after two cars crashed.
The collision involved a blue Ford S-Max travelling west and a grey Mini Cooper heading in the opposite direction.
The Mini driver, a 31-year-old man from Berkshire, was taken by air ambulance to Queens Hospital, Romford where he is being treated for serious leg injuries.
The S-Max driver had minor injuries but her passenger, a woman in her 30s who is five months pregnant, was detained at Royal London Hospital for observation.
The road was closed for more than five hours while fire crews freed the trapped Mini driver, vehicles were recovered and police carried out initial investigations.
Officers want to trace the driver of a white Ford Transit van which was at the scene at the time of the collision but drove away. The vehicle was not damaged but police want to talk to the driver, who is thought to operate locally, about events leading to the collision.
Any witnesses or anyone with information about the van and its driver, should contact the investigating officer Pc Steve Smith at Chigwell road policing office on 101.