A man with an automatic rifle kept his two young daughters by his side as he held Prince William County police at bay yesterday during a three-hour confrontation at a Woodbridge truck rental agency.

Police said Mark Hultz, 24, grabbed the weapon from his pickup about 1:15 p.m. after a brief conversation with two officers from the Prince William police juvenile unit at his work place, a U-Haul branch at 14523 Telegraph Rd.

Hultz, who lives in the 7500 block of Prince Cole Street in Manassas, voluntarily released the children to a friend and turned himself in to po-lice at 4:45 p.m., according to officer Sam Walker.

Hultz, a mechanic, was charged with brandishing a firearm.

Hultz said he was distraught over the possibility of losing custody of 3-year-old Elizabeth and 2-year-old Renee to his estranged wife Sherry, who has moved to Muncie, Ind., Walker said.

Police evacuated several offices and a day care center near the U-Haul agency and closed a half-mile section of Telegraph Road near Opitz Boulevard during the confrontation.

No shots were fired, and Hultz vowed several times that he would not harm the children, Walker said.

The incident began yesterday morning when a woman hired by Hultz to baby-sit with the children called him at work to say that she would not take part in what she suspected was an abduction, Walker said.

Hultz's daughters have been with him since he visited Muncie a few days ago, Walker said, adding that no abduction charges had been filed in Indiana.

After hearing from the baby sitter, Hultz picked up the children and drove them to his work place, where he was met a short time later by the police juvenile officers.

The officers apparently were notified by the baby sitter, police said.

Hultz was released yesterday on $1,000 bond. He could not be reached for comment.

Petie Madrid, who described himself as a close friend, said Hultz recently had been brooding about his family situation. "He's been upset about this for the last six to eight months," Madrid said. "He wants his kids."