CHICAGO —The prime suspect in the1982 Tylenol murders has been found dead.

According to police in Cambridge, Massachusetts, James Lewis was found unresponsive on Sunday just after 4 p.m. He was pronounced dead shortly after. 

Police said his death was “determined to be not suspicious.”

In 1982, seven people in the greater Chicago area died after taking Tylenol laced with cyanide. 

Soon after, a man wrote an extortion letter to Johnson & Johnson and its subsidiary, the maker of Tylenol, demanding $1 million to stop the killings. 

Lewis was identified as the source of the letters, and was convicted of trying to extort $1 million from Johnson & Johnson in the days after the cyanide-laced pills showed up on store shelves. He spent a dozen years in prison for the attempted extortion. 

For 40 years, he remained a person of interest in the actual killings, but was never charged with the murders.

Sources tell CBS Chicago this is a frustrating day for law enforcement who’ve been investigating the case for decades. The station’s reporting uncovered Lewis was a prime suspect since Day One, and some officials felt they had sufficient circumstantial evidence for Lewis to be charged. 

CBS Chicago Investigators began re-examining the case in April; reporter Brad Edwards traveled to Massachusetts in 2022 to try to track down Lewis. 

He was living at the very same Cambridge apartment he moved into after being released from prison, and Edwards interviewed him there.

He was the only living known person of interest and had not been seen or heard from in more than a decade.

CBS Chicago also interviewed family members, attorneys and law enforcement officers whose lives were forever impacted by the murders. They include members of the Janus family, who lost three loved ones — brothers Adam, 25; Stanley, 27; and Stanley’s wife Theresa, 20 — after they consumed Tylenol.