Musannaf Ibn Abi Shayba 37:601

Yahya ibn Adam narrated to us, he said: Abu Bakr ibn Ayyash narrated to me, from Mughira, from Ibrahim, from Alqama, who said: I said to al-Ashtar: "I was averse to the Day of the House (the day Uthman was besieged), so how did you change your opinion?" He said: "Yes, by Allah, I was indeed averse—(very) averse—to the Day of the House. But I came with Umm Habiba bint Abi Sufyan to bring her into the house, and I wanted to take Uthman out in a litter, but they refused to let me, and they said: 'What is between us and you, O Ashtar?' But I saw Talha and al-Zubayr and the people pledging allegiance to Ali willingly, not coerced, then they broke their pledge to him." I said: "Then is it Ibn al-Zubayr who said: 'Kill me and Malik'?" He said: "No, by Allah, and I did not lift the sword from Ibn al-Zubayr while I saw that there was still some spirit in him, because I was enraged at him for belittling the Mother of the Believers until he brought her out. When I met him, I was not satisfied with the strength of my forearm against him, so I stood up in the stirrups and struck him on his head, and I thought I had killed him." "But the one who said 'Kill me and Malik' was Abd al-Rahman ibn Attab ibn Asid. When I met him, I embraced him, and he and I fell from our horses. He began to call out: 'Kill me and Malik,' and the people were passing by not knowing who he meant, and he did not say 'al-Ashtar,' otherwise I would have killed him."