At the end of WW2, Germany was split and controlled by the Allies over 4 zones, but tensions between the democratic West and communist Russia led to the building of the Berlin Wall. The former German Democratic Republic (East Germany) retained the Soviet influence and West Germany, influence from the west. The Ministry for State Security (German: Ministerium für Staatssicherheit, MfS) or Stasi was formed, following the model of the KGB and acted as a secret police machine, gathering information on the sixteen million population. Although starting small, they grew to be one of the most feared and despised organisations in existence. Using tactics of collaboration, threat, surveillance, counter-intelligence and espionage to collect and document their own people, they went to extraordinary lengths to invade the lives of every East German. They were finally shut down in 1990 and their documents became available to all who were surveilled . Parallels can be seen in some information gathering techniques used by modern governments.