Musannaf Ibn Abi Shayba 36:252

Ahmad ibn Abdullah narrated to us, he said: Abu Bakr narrated to us, from Yazid, from Miqsam, from Ibn Abbas, who said: When Hamza was killed on the day of Uhud, Safiyya came seeking him, not knowing what had been done to him. He said: She met Ali and al-Zubayr. Ali said to al-Zubayr, "Tell your mother," and al-Zubayr said, "No, rather you tell your aunt." She said, "What has become of Hamza?" They both showed her that they did not know. He said: Then the Prophet, peace and blessings of Allah be upon him, came and said, "I fear for her sanity." He said: So he placed his hand on her chest and prayed for her. He said: She then recited the *istirja* (saying "To Allah we belong and to Him we shall return") and wept. He said: Then he came and stood over him, and he had been mutilated. He said, "Were it not for the grief of the women, I would have left him until he was gathered from the crops of birds and the bellies of beasts." He said: Then he ordered the slain, and he began to pray over them. He said: He would place nine [bodies] and Hamza, then he would say the *takbir* over them seven times. Then they would be removed, and Hamza would be left, then others would be brought, and he would say the *takbir* over them seven times until he finished with them.