The process of the clandestine removal of an individual from a particular country. Exfiltration may require either that the regular exit controls be duped, by use of false documents and disguises, or evaded altogether. Examples of the former include the rescue of American diplomats from hiding in Tehran in 1979 when the U.S. embassy had been occupied by Iranian radicals, and the exfiltration of Ryszard Kuklinsky and Oleg Gordievsky, who were driven out of Poland and the Soviet Union, respectively, in black operations by intelligence officers working under diplomatic cover.