 An @-@ Nasir Yusuf sent a delegation to Hulagu afterward , repeating his protestations to submission . Hulagu refused to accept the terms and so an @-@ Nasir Yusuf called on Cairo for aid . This plea coincided with a successful coup by the Cairo @-@ based Mamluks against the remaining symbolic Ayyubid leadership in Egypt , with strongman Qutuz officially taking power . Meanwhile , an Ayyubid army was assembled at <unk> , just north of Damascus to defend the city against the Mongols who were now marching towards northern Syria . Aleppo was soon besieged within a week and in January 1260 it fell to the Mongols . The Great Mosque and the Citadel of Aleppo were razed and most of the inhabitants were killed or sold into slavery . The destruction of Aleppo caused panic in Muslim Syria ; The Ayyubid emir of Homs , al @-@ Ashraf Musa , offered to ally with Mongols at the approach of their army and was allowed to continue governance of the city by Hulagu . Hama also capitulated without resisting , but did not join forces with the Mongols . An @-@ Nasir Yusuf opted to flee Damascus to seek protection in Gaza . 
