StB  State Security (, ) or StB / ŠtB, was the plainclothes secret police force in communist Czechoslovakia from 1945 to its dissolution in 1990. Serving as an intelligence and counter-intelligence agency, it dealt with any activity that was considered opposition to the Communist Party of Czechoslovakia and the state. From its establishment on June 30, 1945, the StB was controlled by the Communist Party of Czechoslovakia. The Party used the StB as an instrument of power and repression; State Security spied on and intimidated political opponents of the Party and forged false criminal evidence against them, facilitating the communists' rise to power in 1948. Even before Czechoslovakia became a communist state, the StB obtained forced confessions by means of torture, including the use of psychoactive drug, blackmail and kidnapping. After the coup d'état of 1948, these practices developed under the tutelage of Soviet advisers. Other common practices included telephone tapping, permanent monitoring of apartments, intercepting private mail, house searches, surveillance, and arrests and indictment for so-called "subversion of the republic". After the coup, the StB conducted Operation Border Stone to capture citizens who attempted to defect and cross the Iron Curtain. StB was the main supporter of the Red Brigades, an Italian far-left militant organization. In cooperation with the Palestine Liberation Organization, the StB conducted logistic support and training for Red Brigades in PLO training camps in North Africa and Syria. The StB's part in the fall of the regime in 1989 remains uncertain. The reported murder of a student by police during a peaceful demonstration in November 1989 was the catalyst for wider public support and further demonstrations, leading to the overthrow of the communist regime. According to StB agent , he was used to impersonate a fictitious dead student, Martin Šmíd. However, in 1992, the Czechoslovak parliamentary commission for investigation of events of November 17, 1989 has ruled out Zifčák's testimony, stating that "the role of former StB lieutenant L. Zifčák was only marginal, without any connection to critical events and without any active effort to influence these events. Investigation of related circumstances has indisputably proved that L. Zifčák's testimony that attributes a key role in November's events to himself is based on facts, which are either technically impossible and unfeasible, or contradict actions of persons mentioned by him, which aimed to completely different goals." State Security was dissolved on February 1, 1990.