HARTFORD — A reputed Connecticut mobster who authorities say is the last surviving person of interest in the largest art heist in U.S. history has agreed to plead guilty to unrelated weapons charges.

The Hartford Courant reports the plea agreement was reached Tuesday in 80-year-old Robert Gentile's case. It wasn't immediately known what sentence Gentile can expect. Neither his lawyer nor federal prosecutors would comment on the case.

Gentile was indicted after authorities say they seized a .22-caliber Browning semi-automatic pistol and several other weapons during a May search of his Manchester property.

Prosecutors have said they believe Gentile has information about the still-unsolved 1990 heist at the Isabella Stewart Gardner Museum in Boston. Thieves stole artwork worth an estimated $500 million.

Gentile has denied knowing anything about the art heist.