Following the abortive offensive at Chelyabinsk, the White armies withdrew beyond the Tobol. In September 1919 a White offensive was launched against the Tobol front, the last attempt to change the course of events. However, on 14 October the Reds counterattacked, and thus began the uninterrupted retreat of the Whites to the east. On 14 November 1919 the Red Army captured Omsk. Adm. Kolchak lost control of his government shortly after the defeat; White Army forces in Siberia essentially had ceased to exist by December. Retreat of the eastern front by White armies lasted three months, until mid-February 1920, when the survivors, after crossing Lake Baikal, reached Chita area and joined Ataman Semenov's forces.