The Battle of al-Baida or Lake Bakhtegan was fought in 874 or 875. The Saffarids under Ya'qub ibn al-Layth defeated the Kharijite leader Muhammad ibn Wasil.
Ya'qub ibn al-Layth invaded Fars and advanced to Estakhr, seizing Muhammad's treasuries there. Muhammad departed from Khuzestan, and returned to Fars in an attempt to stop Ya'qub. They met near Lake Bakhtegan in August 875, and in the resulting battle, Muhammad, despite having a numerically superior army, was defeated. Muhammad was forced to flee; Ya'qub looted Muhammad's stronghold at Sa'idabad and took control of Fars.
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