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The atomic bombs dropped on Japan at the behest of President Harry Truman in 1945 killed at least 129,000 people. (Universal History Archive/UIG via Getty Images)

The atomic bombs dropped on Japan at the behest of President Harry Truman in 1945 killed at least 129,000 peop... Read More
A possible Russian plot to drop nuclear bombs on London during the Cold War has been revealed.

The top-secret letter of a British atomic expert warning the authorities of a possible attack in 1954 has been shown for the first time, the Mirror has reported.

The National Archives released the handwritten letter from William Penney, an atomic bomb expert who died in 1991, which alleges a Russian attack was planned.