A truck has jack-knifed on the West Gate Freeway - just before the entrance to the Burnley Tunnel - blocking all 4 lanes of traffic.
Traffic is backed up as crews work to remove the truck.
Caller Terry told Triple M's The Hot Breakfast that there were a lot of police on site.
"The truck is not on its side - it's wedged but it doesn't look like it's wedged terribly hard," he said.
Commuters have opened their doors and appear to be having "a picnic on the West Gate."