Robert P. Hanssen, a former FBI agent who spied for Moscow off and on for more than two decades during and after the Cold War in one of the most damaging espionage cases in American history, was discovered dead in his prison cell in Colorado on Monday, federal authorities announced. He was 79.
The Federal Bureau of Prisons said in a statement that Hanssen was found unresponsive just before 7 a.m. at the U.S. Penitentiary Florence, where he was serving a life sentence. He was pronounced dead after lifesaving efforts by emergency medical workers. The statement did not identify a cause.
