SOUTH SALT LAKE — A dump truck transporting a load of dirt rolled on State Street, spilling half its load and slowing traffic for hours during rush hour Wednesday night.

The accident happened about 3:45 p.m., said Salt South Lake Police officer Diane Moro. The truck was exiting westbound I-80 onto State Street when the driver of a car ahead of it "slammed on its brakes."

The woman driving the dump truck tried to slow her truck but apparently panicked, Moro said.

"She was panicked, and she wasn't able to downshift to the (slower) speed," Moro said.

Moro said crews spent several hours digging the dirt away from the truck to remove it from the accident scene and cleaning up the road, backing traffic for blocks.