“During World War II, Klaus Fuchs worked on the Manhattan Project…and later worked on British nuclear projects.” In 1950, the FBI decoded messages that revealed Fuchs as a Soviet spy. “He admitted spying for the Russians since 1942 and passing on details of British and American nuclear technology. The arrest of Fuchs led authorities to several other individuals involved in a spy ring, culminating with the arrest of Julis and Ethel Rosenberg and their subsequent execution.”
