HILO, HAWAII—Scientists from the Hawaii Undersea Research Laboratory at the University of Hawaii have found a World War II-era Japanese submarine in deep water off the coast of Oahu. It was one of five Japanese subs that were captured by the U.S. Navy and sent to Hawaii for study after the war. The I-400 and its two sister ships could each carry three folding-wing seaplanes and had been designed to attack the U.S. mainland. In 1946, the I-400 was scuttled to prevent its advanced technology from falling into the hands of the Soviet Union.