A commercial truck hauling ammonium nitrate exploded Wednesday morning on a highway in Arkansas, killing the driver and creating a massive crater in the road, authorities said.

The explosion happened west of the city of Camden, or about 100 miles south of Little Rock. According to Arkansas State Police, the driver had called 911 early Wednesday to report that his brakes had caught fire.

The driver, 63-year-old Randall McDougal, attempted to extinguish the blaze but was killed when the truck exploded, authorities said.

"It looks like a bomb went off," Camden Fire Chief Robert Medford told the Arkansas Democrat-Gazette. "There's a big hole in the ground on where the truck was at."

The Arkansas Department of Transportation said crews would begin repairing the 15-foot crater once the wreckage from the accident was cleared. The affected road is a low-volume road that carries about 1,300 vehicles per day, department spokesman Danny Straessle said.

State police said that McDougal was employed by Blann Trucking Co. and was hauling ammonium nitrate, which is commonly used in fertilizers, from El Dorado to Texarkana in south Arkansas.