On October 20, 1944, a combined force of Red Army and Yugoslav Partisans liberated the city of Belgrade, Yugoslavia. The liberation of the Yugoslavian city was part of the larger Belgrade Offensive which saw a combined effort by Soviet and Soviet-backed Yugoslavian forces to drive the Axis out of Yugoslavia, cut communication lines between Germany and its ally Hungary, and establish a Soviet strongpoint in the Balkans. Soviet forces began to arrive in Yugoslavia as early as mid-September 1944 and the Soviet 4th Guards Mechanized Corps and the Yugoslav 12th Corps had broken through the lines of Axis resistance to the south of Belgrade. By October 20, Axis troops had withdrawn from the city in order to avoid capture by the advancing Soviet and Yugoslav forces. The retreating Axis forces were also forced to evacuate through the mountains of Bosnia after their original route had been cut off by the Yugoslav 13th Corps and Bulgarian 2nd Army. This in turn prevented these troops from reinforcing the German elements in Hungary. The success of the operation also established a bridgehead in Baranja, allowing the Soviet 3rd Ukrainian Front to cross the Danube for the Hungarian Offensive and continue the Soviet push towards Berlin.