Chitsong was engaged in three serious operations beyond his frontier, one with a Tartar chief named Yenta, another with the Japanese, and the third in Cochin China. Yenta was of Mongol extraction, and enjoyed supreme power on the borders of Shansi. His brother was chief of the Ordus tribe, which dwells within the Chinese frontier. Changtu, the old residence of Kublai, was one of his camps, and it was said that he could bring 100,000 horsemen into the field. The success of his raids carried alarm through the province of Shansi, and during one of them he laid siege to the capital, Taiyuen. Then the emperor placed a reward on his head and offered an official post to the person who would rid him of his enemy by assassination. The offer failed to bring forward either a murderer or a patriot, and Yenta's hostility was increased by the personal nature of this attack, and perhaps by the apprehension of a sinister fate. He invaded China on a larger scale than ever, and carried his ravages to the southern extremity of Shansi, and returned laden with the spoil of forty districts, and bearing with him 200,000 prisoners to a northern captivity. After this success Yenta seems to have rested on his laurels, although he by no means gave up his raids, which, however, assumed more and more a local character. The Chinese annalists state that never was the frontier more disturbed, and even the establishment of horse fairs for the benefit of the Mongols failed to keep them quiet. In Cochin China the emperor gained some gratifying if not very important successes, and asserted his right as suzerain over several disobedient princes. But a more serious and less satisfactory question had to be settled on the side of Japan.