In 1249 fresh alarm rose in Bagdad, for the Mongols advanced to Dakuka and killed Bilban the prefect. In 1250–1 Nassir the Prince of Damascus got a letter of safe-conduct from the Grand Khan and bore it in his girdle. Splendid gifts were a proof of his gratitude and pleasure. Lands between the Euphrates and Tigris were again visited by the Mongols. The districts of Diarbekr and Mayafarkin with Reesain and Sarudj were given over to pillage. The invaders cut down in this raid more than ten thousand people. A caravan which had set out from Harran for Bagdad was attacked by those Mongols, who massacred every man in it. They took a large booty; among other objects they got six hundred camel loads of sugar and cloth stuffs from Egypt, besides six hundred thousand dinars in money. After such splendid robbery they went back to Khelat for enjoyment. A corps under Yassaur, who eight years before that had struck at Malattia, attacked now this city’s environs and slew all the people whom it could reach with a weapon. Kei Kosru had died in 1245. Yzz ud din Kei Kavus with his two brothers, Rokn ud din Kelidj Arslan, and Alai ud din Kei Kubad, had succeeded their father. The names of all three appeared on the coinage, and were mentioned in mosques at public service. Some great lords of Rūm wished Rokn ud din as chief sovereign. Shems ud din of Ispahan, the grand vizir, put many of those partisans to death. He married Yzz ud din’s mother and, wishing to eliminate Rokn ud din, had him sent to the court of Kuyuk with the tribute and presents agreed on in the treaty of submission made recently. When Rokn ud din had appeared at the court of the Grand Khan he and an officer of his suite, Behai ud din Terjuman, accused the vizir of doing to death powerful people who favored Rokn ud din, of marrying the late Sultan’s widow, and of raising a sovereign to the throne without consent or command of the Grand Khan. On hearing this statement, Kuyuk commanded that Rokn ud din take Yzz ud din’s place, and that Terjuman take Shems ud din’s office. When the latter heard of this change he despatched to Kuyuk, Rashid ud din, the prefect of Malattia, with much gold and many jewels. The new order destroyed him and he hoped now that the Grand Khan would revoke it. But when his envoy was nearing Erzerum the newly made Sultan with his vizir were approaching that city. Overcome by the greatness of his task the weak envoy placed his treasures in the stronghold of Kemash and fled with all speed to Aleppo. Terjuman appeared at Malattia very promptly with two thousand Mongols, and proclaimed the new Sultan. Shems ud din wished to take Yzz ud din to the seacoast from Konia, but he was seized and held captive before he could do so. Terjuman then sent Mongols to Konia to torture that active vizir and thus learn where his treasures were hidden; by these men he was finally killed.