Four people were arrested yesterday and held in the shooting death of an 18-year-old woman slain because the killers "just wanted to watch someone die that evening."

Authorities said that when they arrested the four, they also found "a substantial cache of automatic and semiautomatic guns, as well as bombs, as well as a cache of drugs," said Monmouth County prosecutor Alexander Lehrer.

Arrested were Richard Beigenwald, 42; his wife, Diane Biegenwald, 22, and Darran Fitzgerald, 52, all of Asbury Park, and Jennifer Metz, 29, of Bradley Beach.

The two women were held on $500,000 bail each in the Monmouth County Jail and the men were held without bail.

Beigenwald and Fitzgerald were charged with murder in the shooting death of Anna Oleseowitz, and Lehrer said he would seek the death penalty.

Oleseowitz vanished in August, and her body was found two weeks ago in Ocean Township. She had been shot four times in the head.

The men "randomly selected her on the boardwalk in Asbury Park," the prosecutor said. "They offered her a joint and a ride, and as soon as she got in the car, they shot her just to watch her die."

"The only motive they had was that Beigenwald wanted to watch someone die that evening, so he went out and killed someone," Lehrer said. That's why we're seeking the death penalty."