Police found a 16-year-old boy suffering from serious injuries inside a crashed Downham car on Sunday (May 18).
Officers are unable to say whether the teenager was driving the car, which had collided with one moving vehicle and two stationary ones in Downham Way at around 6.30am.
The 16-year-old was taken to a south London hospital. His injuries are described as serious, but are not thought to be life threatening.
Both stationary vehicles were empty, while the driver of the moving vehicle involved did not require hospital treatment.
There has been no arrest and enquiries continue.