NKVD

The People's Commissariat for Internal Affairs (Russian: Наро́дный комиссариа́т вну́тренних дел, romanized: Naródny komissariát vnútrennih del (NKVD), pronounced [nɐˈrodnɨj kəmʲɪsərʲɪˈat ˈvnutrʲɪnʲɪɣ dʲel]), abbreviated NKVD (НКВД ), was the interior ministry of the Soviet Union.
Established in 1917 as NKVD of the Russian Soviet Federative Socialist Republic, the agency was originally tasked with conducting regular police work and overseeing the country's prisons and labor camps. It was disbanded in 1930, and its functions were dispersed among other agencies. Then it was reinstated as an all-union commissariat in 1934.The functions of the OGPU (the secret police organization) were transferred to the NKVD around the year 1930, giving it a monopoly over law enforcement that lasted until the end of World War II. During this period, the NKVD included both ordinary public order activities, and secret police activities. The NKVD is known for political repression and for carrying out the Great Purge under Joseph Stalin. It was led by Genrikh Yagoda, Nikolai Yezhov, and Lavrentiy Beria.The NKVD undertook mass extrajudicial executions of citizens, and conceived, populated and administered the Gulag system of forced labor camps. Their agents were responsible for the repression of the wealthier peasantry. They oversaw the protection of Soviet borders and espionage (which included carrying out political assassinations).
In March 1946 all People's Commissariats were renamed to Ministries. The NKVD became the Ministry of Internal Affairs (MVD).