A West Valley man has been arrested for allegedly planting a car bomb under the hood of his estranged wife's car Wednesday and endangering her life and those of their three children.

The car caught fire at 5:35 a.m. Wednesday just as Donna Wilson turned the key of the car, which was parked in the driveway of her Kearns home, 4895 S. 4800 West.Wilson got her three children, ages 5, 4 and 2, out of the car and called the fire department, Salt Lake County Fire Capt. Bill Brass said.

Firefighters found a pipe-shaped explosive device, wrapped with black electrical tape, wired to the car ignition, Brass said.

"Fortunately, it didn't function the way it was designed to, because the potential for serious injury was there," he said.

The county bomb squad dismantled the device and shot open the trunk of Wilson's car to check for additional explosive devices, Brass said. Bomb experts with police dogs also searched Wilson's house to make sure there were no hidden explosives.

On March 13, firefighters responded to a suspicious fire in the carport of the house, which was scorched but didn't have serious damage, Brass said.

Robert Loring Wilson, 33, was arrested and booked into the Salt Lake County Jail Wednesday for investigation of four counts of aggravated attempted murder, a first-degree felony. He is also being investigated for one count of possession of an explosive device and several counts of violation of a protective order, Salt Lake County deputy Peggy Faulkner said.

Police had also obtained search warrants for Robert Wilson's home, car and workplace to look for additional explosives, Faulkner said.