In the north, aid came to Sheng Shicai's forces on January 24, 1934, in the form of two Soviet brigades, the Altaiskaya and Tarbaghataiskaya, disguised as "White Russian Cossack Altai Volunteer Army" and led by Red Army General Volgin (nickname of future Marshal Rybalko) in the Soviet Invasion of Xinjiang. The Japanese annexation of Manchuria and rumored support for Ma Zhongying's Hui forces were one cause for concern troubling Joseph Stalin, another was the prospect that rebellion in Xinjiang might spread to the Soviet Central Asian Republics and offer a haven to Turkic Muslim Basmachi rebels. Trade ties between Xinjiang and the Soviet Union also gave the Soviets reason for supporting Sheng. Newly appointed Soviet Consul-General in Urumchi Garegin Apresov openly said to Sheng Shicai in May 1933 : "You can develop the province and improve living conditions of the people of different nationalities, develop their culture. But if you let them ( muslim rebels ) to create an Independent State in the South of the province, converting it into the Second Manchuria at the back door of the USSR, we will not be just a side watchers, we will start to act". First request from Sheng Shicai of military support from USSR came in October 1933. In December 1933 Sheng Shicai arrested White Russian Colonel Papengut, who was staunchy anti-Soviet, and executed by demand of Apresov, replacing him by "neutral" General Bekteyev as Commander-in chief of three White Russian Regiments of Xinjiang Provincial Army, thus paving the way for Soviet intervention into Xinjiang.