Man dies in truck crash northwest of Melbourne

A man has died in a truck crash on the Western Freeway in Melbourne's northwest.

Police say the man was driving the truck towards the city about 7.15am today, between the Gisborne Road on-ramp and the Avenue of Honour off-ramp in Darley, when it hit a tree.

The man died at the scene, no one else was injured and it is believed no other vehicles were involved, but the exact circumstances of the crash are being investigated.