Haidar Qassib, the murderer of Shams al-Din 'Ali, now took advantage of the situation. Arriving from Astarabad, ostensibly to hunt down Yahya's killers, he installed Yahya's nephew Zahir al-Din Karavi to rule. Soon afterwards, however, he removed him from power and ruled in his own name. Unfortunately for him, he was unpopular with nearly everyone even before he came to power. As a former member of Shams al-Din 'Ali's party, the supporters of Mas'ud disliked him, and his murder of Shams al-Din 'Ali alienated him from the dervishes. Nasr Allah, Lutf Allah's tutor, allied with Yahya's murderers and rose in revolt in Isfara'in, the second city of the Sarbadars. Haidar moved to put the rebellion down, but before he could he was stabbed to death by an assassin hired by a Hasan Damghani. Lutf Allah now gained control of the state, but he soon came into conflict with Hasan Damghani as well. He was defeated, and in the process Mas'ud's adherents were mostly eliminated.