Qey Shibir (also Key Shibbir, etc., Amharic: ቀይ ሽብር ḳäy šəbbər; 1977–1978) or the Ethiopian Red Terror, was a violent political campaign against competing Marxist-Leninist groups in Ethiopia and Eritrea that most visibly took place after Mengistu Haile Mariam achieved control of the Derg, the military junta, on 3 February 1977. In December 2006, Mengistu was convicted in absentia for his role in the Red Terror while leader of Ethiopia. It is estimated that between 500,000 and 750,000 people were killed over the course of the Qey Shibir.
Following the deposition of Emperor Haile Selassie on 12 September 1974, the Derg was faced with a number of civilian groups competing for control of Ethiopia, most notably the communist Ethiopian People's Revolutionary Party (EPRP). In September 1976, EPRP militants were arrested and executed, at the same time as the EPRP carried out an assassination campaign against ideologues and supporters of the Derg. Although an unsuccessful attempt to kill Mengistu on 23 September was attributed to the EPRP, the first prominent victim of the EPRP's terror was Dr. Feqre Mar'ed, a member of the Political Bureau and All-Ethiopia Socialist Movement (MEISON), another Marxist-Leninist party.
However, the Derg was split by a rivalry between Mengistu and a faction allied against him, which limited his control. This rivalry was resolved at the meeting of the Standing Committee of the Derg on 3 February 1977, at which fifty-eight top Derg officers were killed in an hour-long shootout. Seven of these officers were opponents of Mengistu, including chairman and Lieutenant General Tafari Benti, Captain Almayahu Haile, Captain Mogas Wolde Mikael and Lt. Colonel Asrat Desta, the latter being an avowed Marxist-Leninist: "We are doing what Lenin did. You cannot build socialism without Red Terror." Although two rivals to Mengistu were still alive—Colonel Berhanu Bayeh and Lt. Colonel Atnafu Abate—Col. Berhanu had sided with Mengistu, and Lt. Colonel Atnafu quickly sided with the victor of the bloodbath, leaving Mengistu as the undisputed head of the Derg, and ruler of Ethiopia. A few days later, Mengistu turned his attention to his rivals outside of the Derg, foremost being the EPRP.