A prank is what authorities say led a trucker to think he had explosives aboard his rig, WTOP Radio Network reported.

Virginia State Police say the driver was on the Beltway when someone pulled up next to him and told him if the truck slowed below a certain speed, it would explode.

The driver then dialed 9-1-1 and told the operator he might have explosives. State Police had him pull onto the George Washington Parkway in McLean, VA, where he was stopped for about three hours Monday afternoon. The parkway was shut down.

Investigators found no explosives.

Sgt. Scott Fear of the U.S. Park Police said the man's concerns were considered credible, and no charges were pending.

The whole thing may have been conjured by the movie "Speed," where a bus is rigged to explode if it goes below 50 miles-an-hour, WTOP said.