The exhortations of Ali had no effect. About 20,000 men of Iraq let by Zaid b Hasan, and Mustur bin Fidki openly revolted and laid down their arms. The rebels approached Ali, and calling him no longer their Caliph, but simply Ali, declared "Ali you are appealing to the sword, and they are appealing to the Quran. Let the issue of the caliphate be deferred to the judgment of God's Book". They adopted a hostile attitude, and warned Ali that if he did not submit to their demand, he would meet the same fate as had befallen his predecessor, Othman.
Heartbroken at the treachery of his men, Ali exclaimed with great grief, "Alas, you are deserting me at the critical time of need. Go and join the Syrian coalition against God and His Apostle." The rebels did not rest content with their own revolt. A large section of the army under Ashtar was still fighting, and they were having an upper hand. The rebels demanded that orders should be issued recalling Ashtar from the battlefield. The rebels went to the extent of reproaching Ali. He was accused of being an accomplice in the murder of Othman. He was accused of fighting against the Syrians to quench his thirst for self-aggrandizement. Ali threatened them with grave consequences and they threatened him in turn. The pressure of the rebels increased and Ali feeling helpless had to recall Ashtar from the front. Ashtar returned reluctantly, and a fierce altercation ensued between him and the rebels. Ashtar upbraided them as traitors, hypocrites and villains. In return they reviled him. Because of this revolt in his army, Ali had to suspend action against the Syrians, and thus the victory which was in immediate sight, evaded him. Henceforward misfortune was to stalk the steps of Ali.