The following report also supports that the murder of Uthman was led by Talha...
The following report also supports that the murder of Uthman was led by Talha, and the killers came out to inform their leader that they took care of Uthman: Abzay said: I witnessed the day they went in against Uthman. They entered the house through an opening in the residence of Amr Ibn Hazm. There was a skirmishing and they got in. By God, I have not forgotten that Sudan Ibn Humran came out and I heard him say: "Where is Talha Ibn Ubaydillah?
We have killed Ibn Affan!" Sunni reference: History of al-Tabari, English version, v15, p200 Uthman was besieged in Medina while Imam Ali (AS) was in Khaibar. The Imam (AS) came to Medina and found people gathering at the residence of Talha. Then Imam Ali (AS) went to met Uthman. Ibn Athir wrote: Uthman said to Ali: "You owe me my Islamic right and the right of brotherhood and relationship.
If I have non of these rights and if I were in pre-Islamic era, it would be still shame for a descendants of Abd Munaf (of whom both Ali and Uthman are descendants) to let a man of Tyme (Talha) rob us of our authority." Ali said to Uthman: "You shall be informed of what I do." Then Ali went to Talha's house. There were a lot of people there. Ali spoke to Talha saying: "Talha, what is this condition in which you have fallen?" Talha replied: "O' Abul Hasan!
it is to late!" Sunni reference: al-Kamil, by Ibn Athir, v3, p84 Tabari also reports the following conversation between Imam Ali and Talha during the siege over Uthman: Ali said to Talha: "I ask you by Allah to send people away from (attacking) Uthman." Talha replied: "No, by God, not until the Umayad voluntarily submit to what is right." (Uthman was the head of Umayad).
Reference: History of al-Tabari, English version, v15, p235 Talha even deprived Uthman of water: Abdurrahman Ibn al-Aswad said: "I constantly saw Ali avoiding (Uthman) and not acting as he formerly had. However, I know that he spoke with Talha when Uthman was under siege, to the effect that water skins should be taken to him.
Ali was extremely upset (from Talha) about that until finally water skins were allowed to reach Uthman." Sunni reference: History of al-Tabari, English version, v15, pp 180-181 To know why Imam Ali (AS) deserted Uthman, see the traditions close to the end of this article.