Amursanaa returned to Dzungaria with his 500 warriors as he was deceived in his hope to take the Dzungar throne with the support of the Qing Empire. A faction of the Oirat aristocrats elevated him as Khan of the Oirats in 1756. However, Amursana's followers lacked unity. The decisive battle took place at Sharbal in 1757 when 3,000 Oirat troops fought against a four times outnumbering enemy. After the 17-day battle, Amursana was defeated and fled to Tobolsk in Russia where he died but the Dzungars continued their war against Manchu invasion until 1758. Brutally revenging the Oirat people for their love for freedom, the Qing army carried out the Dzungar genocide, killing every Oirat they met on their way in the territory of the Dzungar Khanate. Of the 600,000 Dzungar population, only 30 thousand survived. Some scholars estimate that about 80% of the Dzungar population were destroyed by a combination of warfare and disease during the Qing conquest of the Dzungar Khanate in 1755–1758. Mark Levene, a historian whose recent research interests focus on genocide, has stated that the extermination of the Dzungars was "arguably the eighteenth century genocide par excellence." The territory of the Dzungar Khanate was then incorporated into the Qing Empire as Xinjiang, which later became a province.