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The NKVD (Народный комиссариат внутренних дел, "People's Commissariat for Internal Affairs") was the Soviet Union's secret police and intelligence agency from 1934 to 1946. It was created by Joseph Stalin to consolidate his power and crush all opposition. The NKVD was responsible for the Great Purge, a period of mass repression in which millions of people were arrested, tortured, and executed.