 The Kirghiz remained a power in Zhetysu until their destruction by the Kara-Khitans in 1124, when most of them evacuated from their center in Tuva back to the Minusinsk Depression, leaving the Karluks to predominate again in Zhetysu.The position of the Karluk state, based on the rich Zhetysu cities, remained strong, despite the failures in wars in the beginning of the 9th century.Yabgu was enriched by profitable trade in slaves on the Syr-Darya slave markets, selling guards for the Abbasid Caliphs, and control over the transit road to China in the sector from Taraz to Issyk Kul.