1) OGPU successor 
Narodnyi komissariat vnutrennykh del (People's Commissariat of Internal Affairs). The commissariat that administered regular police organizations from 1917 to 1946. When the OGPU was abolished in 1934, the NKVD incorporated the security police organization until 1946.
Soviet secret police agency, a forerunner of the KGB (q.v.).[7 related articles]
The Soviet secret police 1934-38, replaced by the KGB. The NKVD was responsible for Stalin's infamous purges. ...
People's Commissariat of Internal Affairs. The commissariat that administered regular police organizations from 1917 to 1946. When the OGPU (q.v.) was abolished in 1934, the NKVD incorporated the security police organization until 1946.
Narodni Komissarat Vnutrennykh Del - Soviet People's Comissariat of Internal Affairs - the predecessor to the KGB, the Soviet internal security organisation 
in the U.S.S.R., the government's secret-police organization (1934–46). Cf.