Shams al-Din 'Ali's successor was a member of the Sabzavari aristocracy named Yahya Karavi. Yahya was forced to deal with Togha Temur, who in spite of the loss of the allegiance of the Ja'un-i Qurban and, in 1349, the Kartids, still was a danger of the Sarbadars. His army of 50,000 dwarfed the Sarbadar army, which numbered only around 22,000. Yahya neutralized the khan by recognizing him as suzerain, striking coins in his name and paying taxes to him. He also promised to visit Togha Temur once a year. He was probably making one of these visits when he arrived in November or December 1353 at the khan's camp of Sultan-Duvin near Astarabad. Yahya and a group of his followers entered the camp and were allowed into Togha Temur's tent. There, they murdered the khan and his courtiers, then put to death the Mongol troops and killed the nomads' herds. With the death of Togha Temur, the last serious contender for the Ilkhanid throne was gone. The Sarbadar lands then expanded to the borders reached by Mas'ud, and then gained even more: the area around Ray, the city of Tus, and Astarabad and Shasman. Yahya, however, was murdered around 1356, possibly at the hands of Mas'ud's adherents. Mas'ud's son Lutf Allah was possibly involved in the murder.