Police and emergency services responded to reports of a collision in Oakleigh this morning (14 August).
Investigators have been told the vehicle was travelling north on Warrigal Road when it collided into the rear of a truck which was also travelling north, just metres before the intersection of North Road about 4am.
The female driver and sole occupant of the vehicle, was taken to hospital with life-threatening injuries.
She is yet to be identified.
The male truck driver was physically un-injured.
The exact cause of the collision is yet to be determined and the investigation remains ongoing.
North bound traffic on Warrigal Road is being diverted until further notice and police are asking motorists to avoid the area.
Anyone who witnessed the collision or with dash cam footage is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au