FRANKLIN PARK, Allegheny County — A fiery crash this morning shut down part of Interstate 79, causing headaches for morning commuters south of Butler County.

No one was apparently seriously injured in the wreck shortly after 5 a.m. about 200 yards north of the Interstate 279 split in Franklin Park, authorities said.

The crash happened in the right, southbound lane where a small car slammed into the back of a tandem axle truck hauling road salt.

The hood of the car became wedged under the frame of the truck and caught fire, said Bob Jarvis, president of the Franklin Park Volunteer Fire Company.

A short time later, the fire spread to the truck’s rear tires.

The occupants were out of both vehicles by the time state police and fire crews arrived.

Firefighters used compressed air foam to eventually put out the stubborn fire.

The names of the driver and any passengers were not known. The extent of any injuries also was not known.

All southbound lanes were closed for at least one hour before one lane was reopened. Normal southbound traffic was restored about 7:15 a.m.

Jarvis said the highway was icy in spots but he did not know if road conditions were a factor in the crash.