Military counterintelligence of the Soviet Army

Military counterintelligence within the Soviet Armed Forces was controlled by the nonmilitary Soviet secret police throughout the history of the USSR (1922 to 1991). Military counterintelligence departments of the Soviet Armed Forces existed in all larger military formations, usually called a Special Department (Russian: Особый отдел (ОсО), romanized: Osoby otdel, POPsO) or third department/section.

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