Major Collision Investigation Unit detectives are on scene following a multi-vehicle collision in Glenroy.
It's alleged a white truck with a trailer collided with a silver Ford Falcon whilst travelling north-bound on Pascoe Vale Road around 6.20am.
The Ford was forced into oncoming traffic resulting in another collision with a black Nissan Navara ute driving in the opposite direction.
A man believed to be in his mid-thirties driving the Ford has been taken to hospital with life-threatening injuries.
Police are searching for the driver of the truck who left the scene shortly after the incident.
Pascoe Vale Road has been closed in both directions between the Western Ring Road and Glenroy Road.
Drivers are urged to avoid the area for the rest of the morning.
Police are urging anyone who may have witnessed the incident, has any information, or has relevant dash came footage to contact Crime Stoppers on 1800 333 000 or submit a confidential crime report at www.crimestoppersvic.com.au.
