The armies under Kolchak were eventually forced on a mass retreat east. Soviet forces advanced east, despite encountering resistance in Chita, Yakut and Mongolia. Soon the Red Army split the Don and Volunteer armies, forcing an evacuation in Novorossiysk in March and Crimea in November 1920. White resistance was sporadic for two years until the collapse of the White Army in Yakut in June 1923, but went on in Central Asia and Khabarovsk Krai until 1934. There were an estimated 7 to 12 million casualties during the war, mostly civilians.