https://en.wikipedia.org/wiki/Stasi

The Ministry for State Security (German: Ministerium für Staatssicherheit, MfS) or State Security Service (Staatssicherheitsdienst, SSD), commonly known as the Stasi (IPA: [ˈʃtaːziː]),[n 1] was the official state security service of the German Democratic Republic (East Germany). It has been described as one of the most effective and repressive intelligence and secret police agencies ever to have existed.