Służba Bezpieczeństwa

The Służba Bezpieczeństwa Ministerstwa Spraw Wewnętrznych (Polish pronunciation: [ˈswuʐba bɛspʲeˈt͡ʂɛɲstfa miɲiˈstɛrstfa ˈsprav veˈvnɛntʂnɨx]; Security Service of the Ministry of Internal Affairs; Polish abbreviations: SB and MSW, respectively), commonly known as Esbecja, was established in the People's Republic of Poland in 1956. The Ministry of Internal Affairs had been established in 1954, but it didn't play a significant role until the winding-up of the Committee for Public Safety.

It was the main security organization in Poland from 1956 until the end of the People's Republic in 1989.

The post-World War II Ministry of Public Security (MBP) was responsible for security, intelligence and counterintelligence. It controlled over 41,000 soldiers of the Internal Security Corps, 57,500 members of the citizen militia, 32,000 border troops, 10,000 prison officers and 125,000 members of the Volunteer Reserve Citizen Militia.

After the 1954 defection to the West of Józef Światło (born Izaak Fleischfarb), a high-ranking Ministry of Public Security officer instrumental in arresting Cardinal Stefan Wyszyński, this Ministry of Public Security was abolished.

In December 1954, the Communist Party divided the old MBP into two parts: the Committee for Public Security (Komitet do spraw Bezpieczeństwa Publicznego, or KDSBP) and the Ministry of Internal Affairs (MSW). The former was a secret police responsible for internal and external intelligence and counterintelligence to fight underground movements and the influence of the Catholic Church. The MSW was responsible for administrative duties, and eventually controlled the Internal Security Corps, militia, border troops, prison guards and the Volunteer Reserve Citizen Militia.

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Wikipedia