Police are appealing for witnesses following a road traffic collision in Townley Road, Bexley.
Officers were called at approximately 14:55hrs on Tuesday, 8 December following a collision between a car and a pedestrian at the location.
The London Ambulance Service and London's Air Ambulance attended the scene.
The pedestrian, a woman aged 83, was taken to an east London hospital where she remains in a critical condition - her injuries are being treated as life threatening.
Next of kin have been informed.
The car stopped at the scene. The driver was not arrested.
Officers from the Serious Collision Investigation Unit based at Catford investigate - anyone who witnessed the collision or who has information to assist the investigation is asked to contact the witness appeal line on 020 8285 1574.