After their 1287 invasion, the Mongols continued to control down to Tagaung but refused to fill the power vacuum they had created farther south. Indeed, Emperor Kublai Khan never sanctioned an actual occupation of Pagan. His real aim appeared to have been "to keep the entire region of Southeast Asia broken and fragmented." At Pagan, one of Narathihapate's sons Kyawswa emerged king of Pagan in May 1289. But the new "king" controlled just a small area around the capital, and had no real army. The real power in Upper Burma now rested with three brothers, who were former Pagan commanders, of nearby Myinsaing. When the Hanthawaddy Kingdom of Lower Burma became a vassal of Sukhothai in 1293/94, it was the brothers, not Kyawswa, that sent a force to reclaim the former Pagan territory in 1295–96. Though the army was driven back, it left no doubt as to who held the real power in central Burma. In the following years, the brothers, especially the youngest Thihathu, increasingly acted like sovereigns.