The Muslim military officer Sa`d ibn Abi Waqqas quickly seized Valashabad and made a peace treaty with the inhabitants of Weh Antiok Khusrau and Veh-Ardashir. The terms of the treaty were that the inhabitants of Weh Antiok Khusrau were allowed to leave if they wanted to, but if they did not, they were forced to acknowledge Muslim authority, and also pay tribute ("jizya"). Later on, when the Muslims arrived at Ctesiphon, it was completely desolated, due to flight of the Sasanian royal family, nobles, and troops. However, the Muslims had managed to take some of troops captive, and many riches were seized from the Sasanian treasury and were given to the Muslim troops. Furthermore, the throne hall in Taq Kasra was briefly used as a mosque. The Ctesiphon library was also destroyed by the Arabs of the Rashidun Caliphate.