Michigan State Police said it happened about 6:20 a.m. on the northbound Southfield Freeway exit ramp to 7 Mile Road. A car pulled up alongside the semi truck and someone from inside the car fired multiple shots at the truck. The car was last seen traveling westbound on 7 Mile Road.
No in juries were reported. No arrests have been made.
State police troopers shut down the exit ramp so they could investigate.
The investigation is ongoing.