A woman has been critically injured following a single vehicle crash in Werribee on Monday.
Police have been told the car was seen travelling on Synnot Street when it left the road and crashed into a power pole and tree at about 2.25am on December 11.
A woman aged in her 20s, who was a passenger in the car, has been taken to hospital with life-threatening injuries.
The male driver, also aged in his 20s, has been taken to hospital with serious injuries.
Police are investigating whether speed was a factor in the crash after witnesses described hearing the car coming.
Synnot Street is currently closed between Bridge and Cherry streets and the intersection of Duncans and Synnot streets is fully blocked, while police process the scene and investigate the circumstances surrounding the crash.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000 or www.crimestoppersvic.com.au.