In the third lunar month of 215, Cao Cao launched a campaign against Zhang Lu in Hanzhong commandery. When Cao Cao's army arrived at Chencang (陳倉; present-day Chencang District, Baoji, Shaanxi) and was about to pass through Wudu (武都; around present-day Longnan, Gansu), the Di tribes in the area blocked their path, so Cao sent Zhang He, Zhu Ling and others to attack the Di and clear the way. In the fourth month, Cao Cao's army passed through San Pass (散關) and arrived at Hechi (河池). The Di king, Dou Mao (竇茂), led thousands of tribesmen to resist Cao Cao, but Cao defeated them by the following month and he massacred the Di population. Qu Yan (麴演), Jiang Shi (蔣石) and other generals from Xiping (西平) and Jincheng (金城) killed Han Sui and sent his head to Cao Cao.