A tractor-trailer fire Tuesday afternoon closed a portion of Route 30 near Mountville and snarled traffic for rush-hour commuters.

The truck became engulfed in flames after a fire started in its engine compartment, according to Mountville Deputy Chief Robert Evans III.

Fire crews, who were dispatched at 2:35 p.m., remained on the scene until just after 5 p.m.

The incident shut down the eastbound lanes of Route 30 between the Prospect Road and Mountville exits, and fire police diverted traffic to Route 462, according to a dispatcher.

The driver of the truck wasn't injured, Evans said.