POLICE are investigating a fatal collision in Kalkallo on Wednesday afternoon.
It is believed a truck and two cars were all travelling north on the Hume Freeway near Donnybrook Road when the smash occurred about 4pm.
A 59-year-old Wallan woman driving one of the cars died at the scene.
The other car driver, a 52-year-old woman, was taken to the Royal Melbourne Hospital in a critical condition.
The truck driver, a 45-year-old Adelaide man, was taken to the Northern Hospital.
South-bound traffic on the Hume Freeway was diverted at Mitchell Street and north-bound traffic was disrupted for most of the afternoon.