The incident between a car and a pedestrian happened in Rectory Road at 10.19pm yesterday (September 10).
Emergency services, including the London Fire Brigade and London Ambulance Service, attended the scene.
The pedestrian, a woman, was taken to hospital in a serious condition.
Her injuries are not believed to be life-threatening or life-changing.
The driver of the car, a 37-year-old man, was arrested on suspicion of causing serious injury by dangerous driving.
He was taken to hospital as a precaution before being discharged and taken into police custody.
Enquiries into the crash are ongoing and the road has since reopened.
