A motorcyclist was left in a critical condition following crash near Upton Park, police said.
Officers are appealing for witnesses after they were called by the London Ambulance Service (LAS) at approximately 12.15am on Sunday, May 29 to reports of a serious crash between a car and a motorcycle in Barking Road.
The male motorcyclist was taken by LAS to an east London hospital where he remains in a critical condition.
The driver of the car stopped at the scene.
Detectives from the Met's Roads and Transport Policing Command are investigating.
Officers would like to speak with anyone who witnessed the collision or the moments leading up to it.
Information to the witness appeal line at Chadwell Heath Traffic Garage on 020 8597 4874 or via 101.
The Met Police said enquiries continue and there have been no arrests.