Fu Zuoyi
In August 1936 Demchugdongrub's army attempted to invade eastern Suiyuan, but it was defeated by Yan Xishan's forces under the command of Fu Zuoyi. Following this defeat, Demchugdongrub rebuilt his armed forces and planned another invasion. Japanese agents carefully sketched and photographed Suiyuan's defenses while Demchugdongrub was rebuilding his armed forces.