Reds re-captured the city on 8 September 1918 following a counteroffensive. On the 11th Simbirsk fell, and on 8 October Samara. The Whites fell back eastwards to Ufa and Orenburg. In Omsk the Russian Provisional Government quickly came under the influence and later the dominance of its new War Minister, Rear-Admiral Kolchak. On 18 November a coup d'état established Kolchak as dictator. Two members of the Directory were arrested, and subsequently deported, while Kolchak was proclaimed "Supreme Ruler", and "Commander-in-chief of all land and naval forces of Russia." By mid-December 1918 White armies had to leave Ufa, but they balanced that failure with a successful drive towards Perm, which they took on 24 December. Central Asia (1918) In February 1918 the Red Army overthrew the White Russian-supported Kokand autonomy of Turkestan. Although that move seemed to solidify Bolshevik power in Central Asia, more troubles soon arose for the Red Army as the Allied Forces began to intervene. British support of the White Army provided the greatest threat to the Red Army in Central Asia during 1918. Britain sent three prominent military leaders to the area. One was Lieutenant Colonel Frederick Marshman Baile, who recorded a mission to Tashkent, from where the Bolsheviks forced him to flee. Another was General Wilfrid Malleson, leading the Malleson Mission, who assisted the Mensheviks in Ashkhabad (now the capital of Turkmenistan) with a small Anglo-Indian force. However, he failed to gain control of Tashkent, Bukhara and Khiva. The third was Major General Dunsterville, who was driven out by the Bolsheviks of Central Asia only a month after his arrival in August 1918. Despite setbacks because of British invasions during 1918, the Bolsheviks continued to make progress in bringing the Central Asian population under their influence. The first regional congress of the Russian Communist Party convened in the city of Tashkent in June 1918 in order to build support for a local Bolshevik Party. Left SR uprising On 6 July 1918, two Left Socialist-Revolutionaries and Cheka employees, Yakov Blumkin and Nikolai Andreyev, assassinated the German ambassador, Count Mirbach. In Moscow a Left SR uprising was put down by the Bolsheviks, mass arrests of Socialist-Revolutionaries followed, and executions became more frequent. Chamberlin noted, "The time of relative leniency toward former fellow-revolutionists was over. The Left Socialists Revolutionaries, of course, were no longer tolerated as members of the Soviets; from this time the Soviet regime became a pure