The Ministry for State Security, commonly known as the Stasi (German: [ˈʃtaːziː]), was the state security service of the 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 "Shield and Sword of the Party" (Schild und Schwert der Partei). 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 Enlightenment, or Head Office A (German: Hauptverwaltung Aufklärung). They also maintained contacts and occasionally cooperated with West German terrori