loan them to those without, to be animals of burden, with the lease being paid for by those without cattle by tilling the grounds of the cattle owners, increasing the efficiency of the farmlands greatly. In 444, the first major incident of much political infighting during Emperor Taiwu's late reign occurred. Dugu Jie (獨孤絜), a high-level official, who had opposed attacking Rouran, was accused by Cui Hao of being so jealous of Cui, whose suggestions of attacking Rouran were accepted by Emperor Taiwu, that he sabotaged Emperor Taiwu's war efforts by giving the generals the wrong times for rendezvous, and then further planning to have Emperor Taiwu captured by Rouran and then making Emperor Taiwu's brother Tuoba Pi emperor. Emperor Taiwu put Dugu to death, and Tuoba Pi died from anxiety. Further, because Dugu implicated them while being interrogated, fellow officials Zhang Song (張嵩) and Kudi Lin (庫狄鄰) were also put to death. In summer 444, eight nephews of the Tuyuhun khan Murong Muliyan (慕容慕利延), after their brother Murong Weishi (慕容緯世) had been put to death by their uncle, surrendered to Northern Wei and suggested that he attack Tuyuhun. In response, Emperor Taiwu sent his son Tuoba Fuluo (拓拔伏羅) the Prince of Jin to attack Tuyuhun and defeated Tuyuhun forces, forcing Murong Muliyan to flee into the Bailan Mountains (白蘭山, in modern southwestern Qinghai). In 445, with Emperor Taiwu's distant cousin Tuoba Na (拓拔那) the Prince of Gaoliang in pursuit, Murong Muliyan fled west and occupied Yutian (Khotan). (However, after a few years, Tuyuhun would return to its original position.) In 445, angry that Zhenda (真達), the king of Shanshan had refused Emperor Taiwu's messengers passage through Shanshan to other Xiyu kingdoms, Emperor Taiwu sent his general Tuwan Dugui (吐萬度歸) to attack Shanshan, and by fall 445 Zhenda had surrendered. Northern Wei occupied Shanshan. In fall 445, responding to prophecies that "Wu" would destroy Wei, a Xiongnu man, Gai Wu, started an uprising against Northern Wei at Xingcheng (杏城, in modern Yan'an, Shaanxi), and he was quickly joined by a large number of other Xiongnu and Han people. Gai also submitted as a vassal to Liu Song, seeking Liu Song aid. Initial attempts by local officials to stamp out Gai's rebellion failed, and Gai became stronger and stronger, claiming the title of Prince of Tiantai. In spring 446, Emperor Taiwu personally attacked and defeated Gai's ally, the Han rebel Xue