Detectives are appealing for information following a serious collision in Waltham Forest.
Police were called at about 06:15hrs on Thursday, 31 August to Lea Bridge Road, E10, near the junction with Elm Park Road, to reports of a road traffic collision.
Officers attended along with the London Ambulance Service and London's Air Ambulance and found a female pedestrian, aged 19, in collision with a car.
She was taken to an east London hospital with serious head and leg injuries. Her injuries are described as life-threatening.
The driver of the car also received treatment from paramedics at the scene.
Road closures were put in place while emergency services dealt with the incident.
The driver of the car was interviewed under caution at an east London police station in connection with the collision.
There have been no arrests and enquiries continue.
Officers from the Met's Serious Collision Investigation Unit (SCIU) are investigating and are appealing for any witnesses to come forward.
Anyone with information should contact the SCIU on 020 8597 4874, or call 101 or Tweet @MetCC.
Information can also be reported anonymously to Crimestoppers on 0800 555 111 or online at crimestoppers-uk.org