Cleanup operations were scheduled to start Friday on I-15 in eastern Idaho, where an Air Force Minuteman III missile transporter truck rolled Thursday, closing the freeway for seven hours.

The missile's solid rocket fuel is "very stable and not of a substance that detonates," said Marilu Trainor a spokeswoman for Hill Air Force Base. She said teams from Hill and the Idaho State Police had secured the area, making sure there was no leaking gasoline.It could take about two days to clear the wreckage and load the missile's stages for hauling to Hill. The freeway will be closed periodically during that time, she said.

The accident occurred about 11:20 a.m. 20 miles north of Idaho Falls near the intersection of I-15 and Idaho 33. The vehicle had left Malstrom Air Force Base in Montana en route to Hill, near Ogden, for routine maintenance. The transporter carried no warhead.

The driver, identified as Barry Hatch, 35, was admitted to Eastern Idaho Regional Medical Center in Idaho Falls about 25 miles away for treatment of a broken arm and minor injuries.

The driver is a civilian employed by Uinta Freight Lines, Salt Lake City.

"This transporter was only carrying three solid rocket motors connected by their inner stages," said Len Barry, spokesman for Hill. "The three stages of the missile were approximately 45 feet long and six feet in diameter, and weighed approximately 50,000 pounds." A team of experts from Hill planned to dismantle the missile into its stages and haul it to the base.

Although officials stressed that the chance of an explosion was extremely small, they asked the public to stay out of the area in the interest of safety.

An Air Force safety board was formed to investigate the accident.

Hill is the worldwide systems manager for all the Air Force ICBM missiles. Hill is the site of the Air Logistics Center, where the government services Minuteman and MX missiles.