Uthman. Assassination of Uthman As their grievances mounted, discontented groups from provinces began arriving in Medina in 35/656. On their first attempt, the Egyptian opposition sought the advice of Ali, who urged them to send a delegation to negotiate with Uthman, unlike Talha and Ammar ibn Yasir, who might have encouraged the Egyptians to advance on the town. Ali similarly asked the Iraqi opposition to avoid violence, which was heeded. He also acted as a mediator between Uthman and the provincial dissidents more than once to address their economical and political grievances. In particular, he negotiated and guaranteed on behalf of Uthman the promises that persuaded the rebels to return home and ended the first siege. Ali then urged Uthman to publicly repent, which he did. The caliph soon retracted his statement, however, possibly because his secretary Marwan convinced him that repentance would only embolden the opposition. On their way back home, some Egyptian rebels intercepted an official letter ordering their punishment. They now returned to Medina and laid siege to Uthman's residence for a second time, demanding that he abdicate. The caliph refused and claimed he was unaware of the letter, for which Marwan is often blamed in the early sources. Ali and another companion sided with Uthman about the letter, and suspected Marwan, while a report by the Sunni al-Baladhuri () suggests that the caliph accused Ali of forging the letter. This is likely when Ali refused to further intercede for Uthman. That Ali was behind the letter is also the opinion of Leone Caetani (). Giorgio Levi della Vida () is unsure, while Wilferd Madelung strongly rejects the accusation, saying that it "stretches the imagination" in the absence of any evidence. In turn, he accuses Marwan, the bellicose secretary of Uthman, while Hugh N. Kennedy holds Uthman responsible for the letter. The caliph was assassinated soon afterward in the final days of 35 AH (June 656) by the Egyptian rebels during a raid on his residence in Medina. Role of Ali in the assassination Ali played no role in the deadly attack, and his son Hasan was injured while guarding Uthman's besieged residence at the request of Ali. He also convinced the rebels not to prevent the delivery of water to Uthman's house during the siege. Beyond this, historians disagree about his measures to protect the third caliph. Ali is represented by al-Tabari () as an honest