WESTFIELD, Mass. (AP) — A man already serving a life sentence for killing two children is also responsible for the disappearance and death of a Westfield teenager more than 20 years ago, Massachusetts law enforcement authorities said Monday.

Lewis Lent Jr. has confessed to killing James Lusher, 16, who was never seen again after leaving his home on a bicycle ride in 1992, Hampden District Attorney Mark Mastroianni said at a news conference. Lent confessed after getting assurance that he would not be tried for the death, the district attorney said.

Lent, a former handyman and janitor from North Adams, was convicted of the 1990 killing of Jimmy Bernardo, 12, of Pittsfield. He also pleaded guilty to the 1993 abduction and slaying of Sara Ann Wood, also 12, of Norwich Corners in central New York. Her body was never found.

Lent gave investigators great detail about Lusher's death, Mastroianni said, including where his body could be found. Police will begin a search of a large pond in Becket on Tuesday, state police Col. Timothy Alben said. He said the pond is 88 square acres and 58 feet deep in some places.

"It's a daunting task," he said.

Lusher, known as Jamie, was last seen pedaling away from his Westfield home on the way to his grandmother's house in nearby Blandford. His bike was recovered in the woods days later, but he was never seen again. Authorities even drained a pond near where the bike was found without success.

Lusher loved riding his bike, loved dogs, loved playing in the woods and loved getting dirty, his sister, Jennifer, said Monday. She described her brother as "a little spark that if you didn't catch it right you missed something awesome."

During his 1996 trial for the slaying of Jimmy Bernardo, prosecutors say Lent had a "master plan" to kidnap children for sex and hide them in his apartment.

Prosecutors said Lent kidnapped Bernardo on Oct. 22, 1990, after luring him inside the Pittsfield movie theater where Lent worked as a custodian. Police said Lent held the boy overnight and then drove him to Newfane, N.Y., about 250 miles away, and strangled him. Hunters found his body weeks later.

Sara Anne Wood disappeared on Aug. 18, 1993, while riding her bicycle near her home.

Lent's lawyers had argued in the Bernardo case that he was not mentally competent to stand trial because he suffered from an unspecified brain disorder. Lent told police and psychologists that he suffers from memory blackouts, sees flashing bright lights and sometimes hears a voice in his head named Stephen — Lent's middle name. He also said he once had an encounter with space aliens.

Psychologists for the prosecution, however, argued that Lent was faking mental illness.

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