Police are appealing for witnesses following a collision on the Beckton stretch of the Westbound A13 at 19:42hrs on Tuesday, 5 March.
A Ford Fiesta, being driven by a 20-year-old male, collided with the footbridge injuring a female passenger of the vehicle.
Police and London’s Air Ambulance attended.
The driver of the vehicle was taken to an east London hospital for treatment to minor injuries.
The female passenger, aged 19, remains in an east London hospital in a critical condition.
Three lanes of the highway were closed until around 0130hrs.
A 20-year-old male was arrested on suspicion of causing serious injury by dangerous driving and breach of bail conditions.
He remains in custody at an east London police station.
Officers from the Roads and Transport Policing Command investigate.
Detective Constable Amy Trencher, said: “I am particularly keen to hear from anyone who has dashcam footage of the incident or of the movements of the vehicle just before the collision.”
Anyone who witnessed this incident but has not yet come forward is asked to call the Serious Collision Investigation Unit on 020 8597 4874, Tweet @MetCC or call Crimestoppers anonymously on 0800 555 111.