With the support of the Police Commissioner Brigadier General Tsige Dibu and the Chief of Security Colonel Werqneh Gebeyehu, on the evening of 13 December 1960, the plotters managed to take hostage several ministers and other important figures present at Guenet Leul palace in Addis Ababa while the Emperor was out of the country. The next day, units of the Imperial Bodyguard surrounded the principal military bases in the capital and took control of the radio station. The Emperor was proclaimed deposed and his son Crown Prince Asfaw Wossen was appointed in his place. However, the rest of the military and the Ethiopian Church rallied to support the Emperor, and by 19 December the coup was crushed, although 15 of the 21 notables taken hostage were killed, including Mulugeta Buli. The hostages were machine gunned in the Green Salon just before the coup leaders retreated from the Palace compound. Among the important personages executed by the Mengistu's forces were Ras Abebe Aregai, the leading anti-fascist resistance leader against the Italian occupation; Ras Seyoum Mangasha Prince of Tigray, Abba Hanna Jimma, the Emperor's confessor, almoner, and administrator of his personal household; Dejazmatch Letyibelu, a prominent resistance leader during the Italian occupation and nobleman with close ties to the Emperor; and several others.