Courtesy of Virginia State Police

A tractor-trailer crashed Monday morning on the New River bridge on Interstate 81, leaving the cab dangling off the side of the bridge with the driver inside and causing a traffic backup that lasted for hours.

The crash happened just before 9 a.m. on northbound I-81 at mile marker 105 at the start of the bridge.

The tractor-trailer drifted off the right side of the road and continued forward on the side of the road for nearly 600 feet, taking out about 200 feet of guardrail, said Sgt. Michael Conroy of the Virginia State Police. The driver, Claude Armstead, 52, of Batesville, Miss., apparently never braked, he said.

The rig struck the concrete side of the bridge and ran up it, leaving the cab hanging off the side of the bridge. The trailer remained on the bridge.

It took crews about an hour and a half to get to Armstead and remove him from the truck, Conroy said. Crews were able to reach him with a ladder truck.

Armstead was taken to a hospital for treatment. He was alert and talking when he was removed from the cab, Conroy said.

A hospital spokesman said Armstead was listed in good condition at Carilion New River Valley Medical Center as of Monday afternoon.

It was unclear what caused him to crash, Conroy said.

Armstead was hauling a load of computers for Williamson Farms in Charleston, Miss., Conroy said. He said the load didn't appear to be damaged. The front of the cab was crushed, though, and it took crews several hours to remove it from the bridge.

Both northbound lanes of I-81 in that area were shut down until just after 11 a.m., when the left lane reopened.

Traffic didn't get moving smoothly again immediately, though, because some of the vehicles that had been stopped behind the crash were blocking the roadway. At least two vehicles had to be jump-started after their batteries died, Conroy said, and another blocked traffic because its driver locked the keys inside it when she got out.

At least two traffic crashes happened in the backup as well, Conroy said, but no one was seriously hurt. In one of those crashes, a car changed lanes quickly and sideswiped another car, which bumped into an ambulance. The ambulance wasn't damaged, Conroy said.