Officials at Sing Sing prison in Ossining said John Esposito, 64, appeared to have died of natural causes, WCBS-TV in New York reported Thursday.
He died Wednesday shortly after a parole hearing, said the Department of Corrections and Community Supervision.
Esposito had kidnapped Katie Beers, a neighbor, and held her in a dungeon under his home until police found her. Esposito claimed that he loved her.
"I'm saddened at the loss of a life, but at the same time I'm happy that John Esposito will never be granted parole or have the opportunity to hurt anyone ever again," Beers, now 30, said in a statement Wednesday night.
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