In 1148, news reached Damascus of a new crusade, called in response to Zengi's capture of Edessa in 1145. Mu'in ad-Din prepared for the inevitable siege, although he had hoped his former alliance with Jerusalem could be restored and that the crusade would attack some other city. When the crusaders arrived in July, according to Ibn al-Qalanisi, Mu'in ad-Din "distinguished himself in combat with them, and displayed a valour, steadfastness and gallantry such as was never seen in any other, never wearying in repelling them nor taking respite from the struggle against them." Mu'in ad-Din reluctantly sent for help from Nur ad-Din and Saif-ad Din Ghazi, whose power he did not wish to see extend as far south as Damascus, and the crusaders besieged the city for only four days before withdrawing. It is possible that Mu'in ad-Din had bribed the crusaders to leave before Nur ad-Din arrived. After this success, the three emirs besieged the castle of Araima in the County of Tripoli, but Mu'in ad-Din was forced to acknowledge Nur ad-Din as his overlord.