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. The members of the Special Department were colloquially called osobists.
TGU (ТГУ КГБ СССР, 3 ГУ КГБ СССР ('third')) functionaries were responsible for protection of the military units and of important servicemen (e.g. commanding officers) against activities of foreign military attaché offices/diplomats.