In the eighth month of the second year of Emperor Tenji, a hundred and seventy Tang warships lay in battle order at the Paekch'on River. The Japanese fleet arrived and fought the Tang forces, but had the worst of it and pulled back. The Tang held their position firmly.
The next day the Japanese commanders and the king of Paekche, without even studying the weather, agreed: "If we race each other to attack, the enemy will fall back of its own accord." They led the disordered Japanese troops straight at the firmly held Tang lines. The Tang ships closed in from left and right and caught them between. The Japanese were routed at once; many fell into the water and drowned, and the ships could not even turn their bows. Echi no Takutsu looked up to heaven and swore an oath, ground his teeth in fury and killed dozens of men, but at last fell in battle. King Pung of Paekche fled to Koguryo by ship with a few followers.
In the ninth month the Paekche fortress of Churyu also surrendered. The people of Paekche lamented to one another, "Today the name of Paekche has come to an end. We will never again visit the graves of our ancestors," and boarded ships bound for Japan.
The year after the defeat, the third year of Tenji, frontier guards and beacon fires were placed on Tsushima, Iki, Tsukushi and elsewhere against an attack by Tang and Silla. In Tsukushi a great embankment was built to hold back water; it was called Mizuki, the Water Fortress. The following year, exiled nobles from Paekche were ordered to build a fortress in Nagato and two more in Tsukushi, Ono Castle and Ki Castle. The traces of the earthworks of these defenses around Dazaifu remain in Fukuoka today.