Musannaf Ibn Abi Shayba 36:546

Abu Usama narrated to us, from Abd al-Malik ibn Abi Sulayman, who said: I heard Abu Layla al-Kindi say: I saw Uthman look out at the people while he was besieged. He said: "O people, do not kill me, and seek to appease [me/the situation]. For by Allah, if you kill me, you will never pray together ever, and you will never fight an enemy together ever, and you will surely differ until you become like this," and he interlaced his fingers. "And O my people, let not my dissension cause you to suffer what befell the people of Nuh, or the people of Hud, or the people of Salih; and the people of Lut are not far from you." He said: And he sent for Abdullah ibn Salam and asked him, and he said: "Refrain, refrain, for it is more effective for your argument." Then they entered upon him and killed him.