The Stasi - short for Ministry of State Security (MfS) - was the SED's most important instrument to keep the East Germans under control. Almost 100,000 employees of the political secret police observed the population extensively, assisted by a large army of informers. Every critical voice was closely monitored.
In the course of autumn 1989, the call for the ministry to be abolished became more and more resonant. In mid-November the GDR government attempted to save the Stasi by renaming it. But the people would not be deceived and they stood their ground. Then tell-tale smoke from chimneys revealed that members of the secret police were destroying files everywhere and eliminating evidence of injustices.
Now there was no stopping the people: within a few days demonstrators occupied most Stasi buildings throughout the country. Only the headquarters in Berlin was still able to continue operating until mid-January 1990. In the larger towns and cities, citizens’ committees dissolved the state security service against all resistance. These committees were spontaneously drawn from the ranks of those occupying the Stasi buildings. They tracked down hundreds of hidden Stasi bases, switching off bugging devices and securing the files.