A man is in a serious condition after being thrown from the cabin of his truck when it collided with another truck and caught fire on the Western Freeway in Bacchus Marsh.
The smash between the two B-double trucks near Halletts Way happened at about 7.40am this morning and has closed all Melbourne-bound lanes of the freeway.
Photos and footage from the scene posted on Twitter by witnesses show plumes of black smoke rising from one of the trucks, which had burst into flames when it came to rest after crossing a concrete barrier.
Ambulance Victoria said in a statement that the driver would be airlifted by ambulance helicopter to The Alfred hospital with head injuries while another man is stable.
Traffic is being diverted through Bacchus Marsh via Bacchus Marsh Road.