Robert Hanssen, the former FBI agent caught selling damaging secrets to the Russians during and after the Cold War, died of natural causes last month inside Colorado’s notorious Supermax prison, the El Paso County coroner found.
An autopsy conducted by the coroner ruled Hanssen, 79, died of metastatic colon adenocarcinoma — or colon cancer.
He was found dead in his cell June 5 at the U.S. Penitentiary ADMAX in Florence.
Hanssen has been called the most damaging spy in U.S. history. The FBI agent, throughout the 1980s and ’90s, provided highly classified national security information to the Russians in exchange for more than $1.4 million in cash, bank funds and diamonds.
He was arrested in 2001 and charged with espionage. The following year, a federal judge sentenced him to life without parole, sparing him the death penalty.
Since 2002, Hanssen has been housed at the notorious Florence prison known as the “Alcatraz of the Rockies,” home to some of the country’s highest-risk inmates.
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