Because of their strategic location, the islands was one of the first points occupied by invading Japanese imperial forces at the outbreak of the Pacific War. The morning of December 8, 1941, the Batan Task Force from Taiwan landed on the Batan Islands, which became the first American territory occupied by the Japanese. The purpose of the invasion was to secure the existing small airfield outside Basco, which was accomplished without resistance. Japanese fighters from Basco took part in the raid on Clark Air Base the following day. However, over the next several days, the success of the Japanese bombing of Clark Field rendered a base at Basco unnecessary, and on December 10, 1941, the naval combat force was withdrawn to participate in the invasion of Camiguin.