Abu Obeidah reminded Kaled of the obligation they were under to protect the Aleppians, now their confederates, who were likely to be exposed to the outrage and cruelty of Youkinna, for, in all probability, he would severely resent their defection. They therefore marched as fast as they could, and when they drew near Aleppo found that they had not been at all wrong in their apprehensions. Youkinna had drawn up his soldiers with the design to fall upon the townsmen, and threatened them with present death unless they would break their covenant with the Arabs and go out with him to fight them, and unless they brought out to him the first contriver and proposer of the convention. At last he fell upon them in good earnest and killed about three hundred of them. His brother John, who was in the castle, hearing a piteous outcry and lamentation, came down from the castle and entreated his brother to spare the people, representing to him that Jesus Christ had commanded us not to contend with our enemies, much less with those of our own religion. Youkinna told him that they had agreed with the Arabs and assisted them; which John excused, telling him, "That what they did was only for their own security, because they were no fighting men." In short, he took their part so long till he provoked his brother to that degree that he charged him with being the chief contriver and manager of the whole business; and at last, in a great passion, cut his head off. While he was murdering the unhappy Aleppians, Kaled (better late than never) came to their relief. Youkinna, perceiving his arrival, retired with a considerable number of soldiers into the castle. The Saracens killed that day three thousand of his men. However, he prepared himself to sustain a siege, and planted engines upon the castle walls.