Klaus Fuchs

The atomic scientist who passed Manhattan Project secrets to Moscow

Overview

Klaus Fuchs, a German born physicist and communist who fled the Nazis to Britain, worked on the British atomic project and then at Los Alamos as part of the British mission to the Manhattan Project. He passed detailed information on the plutonium implosion bomb to Soviet intelligence, helping the Soviet Union test its first bomb in 1949. Identified through VENONA decrypts, he confessed to MI5 in 1950 and served nine years of a fourteen year sentence. His confession led investigators to the courier Harry Gold and on to the Rosenberg network. After his release he moved to East Germany.