The Probert Encyclopaedia of Warfare

DUNCAN

Duncan was the codename of Francesco Constantini, the first Soviet agent to penetrate the British foreign service. He worked as an Italian messenger at the British embassy in Rome, and was recruited in 1924 by the OGPU to pass diplomatic secrets to which he had access to the Soviets. By 1928 it was apparent that agent
Duncan (who worked exclusively for money) was also spying for the Italians, but he continued to work for the Soviets until the 1930s.
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