Alexander Mikhailovich Orlov (Leiba Lazarevich Felbing,) (21 August 1895-25 March 1973) was a Soviet espionage administrator. He defected to the U.S. in 1938. He warned Leon Trotsky of his impending assassination. His expertise made him an obvious candidate for the OGPU, the political police that preceded the NKVD. Wikipedia
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