sentences:  Aybak wrote to an-Nassir Yusuf warning him of the danger of these Mamluks who took refuge in Syria, and agreed to grant him their territorial domains on the coast, but an-Nasir Yusuf refused to expel them and instead returned to them the domains which Aybak had granted.In 1255 an-Nasir Yusuf sent new forces to the Egyptian border, this time with many of Aktai's Mamluks, among them Baibars al-Bunduqdari, and Qalawun al-Alfi, but he was defeated again.An-Nasir had contact and correspondence with the European Crusaders, and tried to reach an accord with the barons of Acre.