James Lewis, who claimed responsibility for the 1982 Tylenol murders, was found dead in Cambridge in an apartment on Gore Street around 4 p.m. on Sunday, July 9, according to the Cambridge Police Department.
He was declared dead shortly after first responders arrived at the scene.
An initial investigation determined that his death was not suspicious.
Lewis wrote a letter to Johnson & Johnson claiming responsibility for tampering with Tylenol products and demanding $1 million, according to the Chicago History Museum. He served 13 years in prison for extortion.
After the 1982 killings, Congress passed an anti-tampering bill that made it a Federal offense to maliciously tamper with products in an attempt to cause death or injury.
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