The Mamluk leader Baibars attacked Krak de Chevaliers in 1271. His army attacked with trebuchets and catapults. Baibars's army got inside the first wall, but they could not take control of the centre of the castle. Baibars wrote a false letter, which he sent to the Crusaders in the castle. They believed the letter had come from an ally of theirs. The letter said that the Crusaders should surrender. They did surrender, and the Mamluk army of Baibars took control of the castle. After this the Mamluks worked on the castle's buildings. Their builders repaired the buildings and fortifications, and they built a large new tower. The new tower was complete in 1285. (Baibars destroyed many other castles that he took from the Crusaders, but not Krak de Chevaliers.) Unlike many Crusader castles, Krak de Chevaliers continued to be a military position and a centre of government in its area. The castle started to be a town of its own. The frescos in the chapel were whitewashed.