At this moment, Khalid gave a signal to his cavalry and they charged the Persian flanks. The Muslim light cavalry could charge at incredible speed, and could successfully attack, retreat, regroup and attack again. This mobility gave them an upper hand on the Sassanid heavy cavalry, resulting in a rout of the Persian cavalry. They attacked the flanks and rear of the Persian army and started encircling it. The main body of the Muslim army under Khalid ibn al-Walid resumed the attack against the Persian front, while at the same time extending its flanks to join with the cavalry and completely surround the Sassanids. The army of Andarzaghar was caught in a trap and could not escape. Recoiling from the assaults that came from all directions, the Sassanid army gathered in an unwieldy mass, unable to use their weapons freely. The battle was over, with heavy casualties inflicted on the Sassanid army. Nevertheless, a few thousand imperial soldiers, and Andarzaghar himself, managed to escape.