brother Li Lin the Prince of Yong tried to mount a challenge against him, seeking to effectively secede with the region south of the Yangtze River, but was quickly defeated and killed by forces loyal to Emperor Suzong. Emperor Suzong's court was also itself filled with internal struggles, with Li Fuguo aligned with Emperor Suzong's favorite concubine Consort Zhang, in opposition to Li Chu, Li Tan, and Emperor Suzong's trusted advisor Li Mi. In early 757, after Li Tan repeatedly accused Li Fuguo and Consort Zhang of corruption, Li Fuguo and Empress Zhang in turn falsely accused him of trying to assassinate Li Chu, who was older than he was, in order to become the heir. Emperor Suzong, in anger, ordered Li Tan to commit suicide, which drew fear from Li Chu and Li Mi. Li Chu considered assassinating Li Fuguo and Consort Zhang, but at Li Mi's urging, stopped his plans to do so. Emperor Suzong, finding it difficult to recapture Chang'an just with his own troops, then entered into an alliance with Huige's Bayanchur Khan Yaoluoge Moyanchuo, where Huige forces arrived at Emperor Suzong's then-headquarters at Fengxiang (鳳翔, in modern Baoji) to join the elite Tang forces recalled from the Anxi Circuit and the Western Regions (Xiyu). (Emperor Suzong did so by promising that the Huige forces would be permitted to pillage the Chang'an region once it was recaptured.) Li Mi suggested that these forces be used to attack Yan's power base at Fanyang first, to root out the possibility of a Yan recovery. Emperor Suzong chose not to do so and decided to attack Chang'an first, with Li Chu in command of the joint forces. The forces recaptured Chang'an in fall 757, allowing Emperor Suzong to rebuild his administration in the capital. (Huige forces were set to pillage Chang'an, but Li Chu bowed to the Huige prince commanding Huige forces to plead to delay the pillage—pointing out that if pillaging were carried out, the people of the eastern capital Luoyang, then serving as Yan's capital, would resist heavily, and asking that Huige pillage Luoyang instead. The Huige prince agreed.) After Emperor Suzong recaptured Chang'an, Li Mi resigned and became a hermit, leaving Li Fuguo, Consort Zhang (who was then created empress), and Li Chu the lead figures at court, and Li Fuguo, in command of the imperial guards, would soon have such paramount powers that even Emperor