BOSTON (AP) — A man who was considered a suspect in the heist of about $500 million worth of artwork from a Boston museum has been released from prison.

The Boston Globe reports that David Turner was freed on Wednesday after serving 21 years for his role in the 1999 planned armed robbery of an armored car.

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According to court records, FBI agents told Turner he was a suspect in the 1990 heist at the Isabella Stewart Gardner Museum and could receive leniency if he returned the stolen masterpieces. Turner said he knew nothing about the theft.

The art, including works by Rembrandt and Vermeer, has never been recovered.

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The 52-year-old Turner will remain on probation for three more years.

Neither Turner nor his lawyer answered questions about the missing art outside of court.

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