A driver ran a checkpoint at a nuclear weapons plant early Monday and crashed into a barrier, then fled on foot, authorities said. Oak Ridge police were searching for the driver.

Guards at the Y-12 plant, a primary storehouse for bomb-grade uranium, said the man "appeared to be impaired in some way" when they stopped him around 5 a.m. at a security checkpoint near a rear entrance, spokesman Bill Wilburn said.

They asked the man for identification, but he hit the gas and drove through the checkpoint. The vehicle crashed 300 yards away into a gate-like security barrier that was activated by guards.

"When he hit that, he jumped out of the car and ran away. He left the car there with the engine still running," Wilburn said.

Wilburn said the guards told him the car had been hot-wired and there were no weapons inside. "They checked the car very thoroughly before they moved it. They found nothing," he said.

Oak Ridge Police Chief David Beams did not immediately return calls for comment.

Steve Wyatt, spokesman for the National Nuclear Security Administration in Oak Ridge, which oversees the Y-12 plant, said the crash was "well away from any sensitive areas of the plant." Y-12 makes and dismantles uranium parts in nuclear warheads.

"The important thing is our (security) system worked as designed and the security police officers did exactly what you do in these situations," he said.