Britain's Most Valuable Cold War Spy Inside KGB Dies at 86

Oleg Gordievsky, a Soviet KGB officer agent who helped change the course of the Cold War by covertly passing secrets to Britain, has died. He was 86.

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Gordievsky died in England, where he had lived since defecting in 1985. Police said they are not treating his death as suspicious. Historians consider Gordievsky one of the era's most important spies. In the 1980s, his intelligence helped avoid a dangerous escalation of nuclear tensions between the USSR and the West.