Orders for the second invasion came in the first lunar month of 1281. Two fleets were prepared, a force of 900 ships in Korea and 3,500 ships in Southern China with a combined force of 142,000 soldiers and sailors. On 15 August, a great typhoon, known in Japanese as kamikaze, struck the fleet at anchor from the west and devastated it. Sensing the oncoming typhoon, Korean and south Chinese mariners retreated and unsuccessfully docked in Imari Bay, where they were destroyed by the storm. Thousands of soldiers were left drifting on pieces of wood or washed ashore. The Japanese defenders killed all those they found except for the Southern Chinese, who they felt had been coerced into joining the attack on Japan. According to a Korean source, of the 26,989 Koreans who set out with the Eastern Route fleet, 7,592 did not return. Chinese and Mongol sources indicate a casualty rate of 60 to 90 percent. Korea, which was in charge of shipbuilding for the invasion, also lost its ability to build ships and its ability to defend the sea since a large amount of lumber was cut down. Later, taking advantage of the situation, the number of Japanese joining the wokou began to increase, and attacks on the coasts of China and Korea intensified.