The Ministry for State Security, commonly known as the (), was the state security service of East Germany from 1950 to 1990. The Stasi's function was similar to the KGB, serving as a means of maintaining state authority, i.e., the "Sword and Shield of the Party" (). This was accomplished primarily through the use of a network of civilian informants. This organization contributed to the arrest of approximately 250,000 people in East Germany. The Stasi also conducted espionage and other clandestine operations abroad through its subordinate foreign intelligence service, the Office of Reconnaissance, or Head Office A (). They also maintained contacts and occasionally cooperated with West German terrorists. The Stasi was headquartered in East Berlin, with an extensive complex in Berlin-Lichtenberg and several smaller facilities throughout the city. Erich Mielke was the Stasi's longest-serving chief, in power for 32 of the 40 years of the GDR's existence. The HVA (), under Markus Wolf, gained a reputation as one of the most effective intelligence agencies of the Cold War. After German reunification, numerous officials were prosecuted for their crimes and the surveillance files that the Stasi had maintained on millions of East Germans were unclassified so that all citizens could inspect their personal file on request. The files were maintained by the Stasi Records Agency until June 2021, when they became part of the German Federal Archives. Creation The Stasi was founded on 8 February 1950. Wilhelm Zaisser was the first Minister of State Security of the GDR, and Erich Mielke was his deputy. Zaisser tried to depose SED General Secretary Walter Ulbricht after the June 1953 uprising, but was instead removed by Ulbricht and replaced with Ernst Wollweber thereafter. Following the June 1953 uprising, the Politbüro decided to downgrade the apparatus to a State Secretariat and incorporate it under the Ministry of the Interior under the leadership of Willi Stoph. The Minister of State Security simultaneously became a State Secretary of State Security. The Stasi held this status until November 1955, when it was restored to a ministry. Wollweber resigned in 1957 after clashes with Ulbricht and Erich Honecker, and was succeeded by his deputy, Erich Mielke. In 1957, Markus Wolf became head of the Hauptverwaltung Aufklärung (HVA) (Main Reconnaissance Administration), the foreign intelligence section of the Stasi. As intelligence chief, Wolf achieved great success in penetrating the government, political and business circles of West Germany with spies. The