Detectives are appealing for witnesses and information following a collision in north London.
Police were called at 19:46hrs on Saturday, 7 January to Marsh Lane in Stanmore following reports of a silver Honda in collision with a street sign.
Officers and the London Ambulance Service attended. The female driver, aged in her 80s, was taken to a central London hospital where she remains in a critical condition.
Detectives from the Met's Roads and Transport Policing Command are investigating.
Anyone who witnessed the collision is asked to contact the Serious Collision Investigation Unit at Alperton on 020 8991 9555 or via 101 and @MetCC