Police said Wednesday they will refer four teenage boys to 3rd District Juvenile Court in connection with a pipe bomb explosion Monday night near the home of former gubernatorial candidate Jon Huntsman.

Salt Lake Police Officer Gary Newren, working off-duty security for Huntsman, 3049 E. Sherwood Drive, heard an explosion about 6:20 p.m. and saw four boys running from the scene.

Newren confronted the juveniles, who told him they had constructed a pipe bomb, buried it in the ground on Huntsman's property and detonated it, according to a police report.

The explosion created a hole 4 feet wide and 3 feet deep.

"There is no threat to the Huntsmans involved," said Lt. Tom Brown.

The boys told officers they had made the bomb with materials purchased at a local hardware store and at a gunsmith shop.