March 1942 that Japan begin attacks on Allied convoys in the Indian Ocean. On 8 April 1942, the Japanese formally agreed to meet this request by dispatching submarines to operate off the coast of East Africa, and that day they withdrew Submarine Division 1 of Submarine Squadron 8 from its base at Kwajalein to Japan. By 16 April 1942 they had created the "A" detachment within Submarine Squadron 8, consisting of I-10 and the submarines , , , and , as well as midget submarines and the auxiliary cruisers and , which were to operate as supply ships for the submarines. That morning, the commander of the 6th Fleet, Vice Admiral Teruhisa Komatsu, the commander of Submarine Squadron 8, their staffs, and the midget submarine crews paid a courtesy call on Admiral Yamamoto aboard his flagship, the battleship , at Hashirajima anchorage. After the visit with Yamamoto, the detachment got underway at 11:00, bound for Penang in Japanese-occupied British Malaya. During the detachment′s voyage, 16 United States Army Air Forces B-25 Mitchell bombers launched by the aircraft carrier struck targets on Honshu in the Doolittle Raid on 18 April 1942. The detachment received orders from the 6th Fleet that day to divert from its voyage and head northeast, passing north of the Bonin Islands, to intercept the U.S. Navy task force that had launched the strike. The detachment failed to find the U.S. ships and soon resumed its voyage. I-30 and Aikoku Maru called at Penang from 20 April to 22 April 1942 before heading into the Indian Ocean to conduct an advance reconnaissance of the "A" Detachment′s planned operating area. I-10 made an overnight stop at Singapore from 23 to 24 April, then proceeded to Penang. The Imperial Japanese Army transport Urajio Maru mistakenly opened gunfire on her during her voyage, but she avoided damage and arrived at Penang safely on 25 April 1942. On 27 April, the rest of the "A" Detachment arrived at Penang, where the seaplane carrier — which had undergone modifications allowing her to carry Type A midget submarines — rendezvoused with it. I-16, I-18, and I-20 each embarked a midget submarine at Penang on 30 April 1942. Indian Ocean operation I-10 and the other "A" detachment units got underway from Penang on 30 April 1942, headed westward into the Indian Ocean with I-10 serving as the detachment′s flagship. The submarines refueled at sea from