The explosive device the prompted the closure of U.S. Highway 20 southbound near Idaho Falls was an altered firework, the Idaho State Police said.
Police say the driver of a car that was found to have an explosive device inside Thursday is a 19-year-old from Rexburg.
Dallin B. Baggett was arrested on charges of possession of marijuana, possession of drug paraphernalia, transporting explosives, and unlawful possession of a bomb or destructive device, which was found in a traffic stop on the highway near Idaho Falls. The Idaho Falls/Bonneville County Bomb Squad detonated it at 11:45 a.m. Thursday.
The device was 6 to 8 inches long and a half inch in diameter.
Sgt. Jeff Edwards of the Bonneville County Sheriff's Office said a car was pulled over on U.S. Highway 20 at milepost 312 (southbound near the St. Leon exit) for a routine traffic stop Thursday morning. A K-9 deputy found drugs in the car. Police also found the device.
A robot took the device several yards away from the highway, where it was detonated.
Southbound traffic, which had been diverted for three hours to the Hitt Road exit, opened shortly after the detonation shortly before noon.