In 179 BC, An Dương Vương acknowledged the suzerainty of the Han dynasty, causing Zhao Tuo of Nanyue to become hostile and mobilize forces against Âu Lạc. Zhao Tuo's initial attack was unsuccessful. According to legend, Zhao Tuo asked for a truce and sent his son to conduct a marriage alliance with An Dương Vương's daughter. Zhao Tuo's son stole the turtle claw that powered An Dương Vương's magical crossbow, rendering his realm without protection. When Zhao Tuo invaded again, An Dương Vương fled into the sea where he was welcomed by the golden turtle. Âu Lạc was divided into the two prefectures of Jiaozhi and Jiuzhen.