The prime suspect in the 1982 Tylenol poisonings that killed seven people in the Chicago Area has died in Massachusetts, the Associated Press reported.

Emergency responders found 72-year-old James W. Lewis dead at his home in Cambridge Sunday afternoon, according to police.

“Following an investigation, Lewis’ death was determined to be not suspicious,” the statement from Cambridge Police Superintendent Frederick Cabral said.

In 1982, seven people, including a 12-year-old girl, died after taking over-the-counter painkillers laced in cyanide leading to nationwide panic and an overhaul in the safety of over-the-counter medication packaging. 

While no one was ever charged in the deaths of the seven people, Lewis served more than 12 years in prison for sending an extortion note to manufacturer Johnson & Johnson where he demanded $1 million to “stop the killing.” 

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1982 Tylenol murders never solved

Officers arrested Lewis in 1982 following a nationwide search. He gave investigators a detailed explanation as to how the killer might have operated and later admitted he sent the letter to Johnson & Johnson. He said he never planned on collecting any money and just wanted to embarrass his wife’s former employer by having money sent to their bank account. 

He later told the Associated Press in prison that his account to investigators was simply an assumption on the killer’s actions, calling the person responsible “a heinous, cold-blooded killer, a cruel monster.”

Lewis was released from prison in 1995, and he and his wife moved to Massachusetts. While remaining a suspect, he always denied any role in the deaths, even going as far as creating a website devoted to claiming he was framed. In 2010, Lewis gave DNA samples to the FBI.