Once they had the hostages in their power, the Khazraj then threatened to kill them unless the Jews handed their lands over to the Khazraj. Some of the Jews were willing to submit, but Ka'b insisted that they should not sacrifice their ancestral homes and so most of the hostages were killed. As a result, the Qurayza and the Nadir allied themselves with the Aws.
After capturing the Jews as hostages, the Khazraj demanded the Jews hand over their land. Some Jews agreed to comply, but Ka'b refused, insisting they not surrender their ancestral homes. Consequently, most of the hostages were killed, leading to an alliance between the Qurayza and Nadir with the Aws.