An apparently suicidal man ran a security barricade in Arizona and was shot dead by deputies hours before President George W. Bush was scheduled to visit a fire-devastated area nearby.

The incident did not appear related to the President's visit, said Steve Easton of the Pima County Sheriff's Office.

The shot man stopped at a highway checkpoint outside Tucson at the base of Mount Lemmon, where a fire in June destroyed more than 300 structures and burned 33,900ha.

The driver seemed intoxicated and when a deputy tried to detain him he drove past the barricade, which had been set up during the fires, Easton said.

Deputies intercepted him about 6km later, and the man told them he wanted to die on the mountain.

After threatening to run over deputies blocking the road, the man steered toward them.

"Fearing for their lives, they shot him," Easton said. The man, whose identity has not been given, was hit 10 times.