One dead, three critical after car collides with truck on South Western Highway

A WOMAN has died and three other people have critical injuries following a horror crash in Waroona this afternoon.

The crash involving a car and a truck happened on South Western Highway near Hall Road just after 4pm.

The woman died at the scene and three males had to be freed from the wrecked car.

Two rescue helicopters and several ambulances were sent to the scene.

One man has been flown to Royal Perth Hospital and the remaining two were taken to hospital by ambulance.

The highway remains closed in both directions tonight and drivers have been advised to avoid the area.

It is not clear what caused the crash but police major crash investigators are at the scene.