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The Organization X (Greek: Οργάνωσις Χ; commonly referred to simply as X ("Chi" in Greek), and members as Chites (Χίτες)) was a paramilitary right-wing anti-communist royalist organization set up in 1941 during the Axis occupation of Greece. Initially an anti-Axis resistance organization, it gradually shifted its focus towards anti-communism. In 1951, X was officially recognized as a National Organization of Internal Resistance by the Greek Ministry of National Defense. Following the end of the Axis occupation, it played an active role in the persecution of communists during the White Terror and various military operations of the Greek Civil War, most notably the Dekemvriana.