Sanjar's catastrophe against the Qara-Khitai

This was a battle between Sultan Sanjar and the army of the Khita (the Qarakhanids) on the first of Safar 536 AH. Ibn Khaldun relates that Sanjar and the Muslims were routed in it, and the killing continued among them. ¹

Ibn Khaldun says that Kuchlug, king of the Khita, ruled Transoxiana. Mahmud Khan ibn Arslan Khan complained to him about the Qarakhanids, and sought help from Sultan Sanjar. Sanjar marched and crossed the river in Dhu al-Qa'da 535 AH, and wrote to their king, calling him to Islam and threatening him. ¹

The Qarakhanids met him on the first of Safar 536 AH. Sanjar and the Muslims were routed, and the lord of Sistan, the amir Qamaj, and the sultan's wife, the daughter of Arslan Khan, were taken captive. ¹

Ibn Khaldun says that there had been no battle in Islam greater than this, nor one with more killing. He adds that power beyond the river was settled among the Khita and the Turks, and that the Muslim Khanid state came to an end. ¹

This report comes from a single source and needs an additional source.