State Security (Държавна сигурност, Darzhavna sigurnost; abbreviated ДС, DS) was the name of the Bulgarian secret service under the People's Republic of Bulgaria during the Cold War, until 1989.

[1] In 1964, the State Security formed Service 7, led by Colonel Petko Kovachev, dedicated to murder, kidnapping, and disinformation against Bulgarian dissidents living abroad.

An issue the international community often raises is State Security's alleged control of the weapons, drugs, alcohol, cigarettes, gold, silver, and antiques trafficked through Bulgaria before 1989.

[3] The agency is often incriminated with the ill-famed murder of dissident writer Georgi Markov and was formerly accused of the 1981 attempt on Pope John Paul II's life.

The operation codenamed "Cross" and the plan was that Bulgarian secret agents would set fire to the Ecumenical Patriarchate of Constantinople in Istanbul and make it look like the work of Turks.