With the opening of 1372 troubles multiplied. Nap T‘ap-chul, a Mongol chieftain at large, together with Ko-gan, led a mixed army of Mongol and Yŭ-jin adventurers across the Yalu and began to harry the northern border. Gen. Chi Yun was sent to put down the presumptuous robbers. At the same time the Quelpart horse-breeders again revolted and when the king, at the command of the emperor, sent a man to bring horses as tribute to China the insurrectionists put him to death. But the common people of Quelpart formed a sort of militia and put down the insurrection themselves. The Japanese also made trouble, for they now began again to ravage the eastern coast, and struck as high north as An-byŭn, and Ham-ju, now Ham-heung. They also carried on operations at Nam-han near Seoul, but in both instances were driven off. It is said that at this time the king was given over to sodomy and that he had a “school” of boys at the palace to cater to his unnatural passions. The people were deeply indignant and talk ran very high, but the person of the king was sacred, and his acts were not to be accounted for; so he went his evil way unchecked, each step bringing him nearer the overthrow of the dynasty which was now not far away. Late in the year the king sent a present of fifty horses to the Ming emperor. No sooner had the spring of 1373 opened than the remnant of the Mongols in the north sent to the king and said “We are about to raise a mighty force to overthrow the Ming empire, and you must cooperate with us in this work.” The messenger who brought this unwelcome summons was promptly clapped into prison, but later at the advice of the courtiers he was liberated and sent back home. It would be well-nigh impossible to describe each successive expedition of the Japanese to the shores of Koryŭ, but at this time one of unusual importance occurred. The marauders ascended the Han River in their small boats and made a swift attack on Han-yang the site of the present capital of Korea. Before leaving they burned it to the ground. The slaughter was terrific and the whole country and especially the capital was thrown into a state of unusual solicitude. The Japanese, loaded down with booty, made their way to the island of Kyo-dong just outside the island of Kang-wha, and proceeded to kill and plunder there.