( and ), and four United States Navy destroyers (, , and ) would be there within three days. Although Durban and Stronghold were available, Admiral Phillips decided to leave them at Singapore because they were not as fast as the other units. Additionally, Danae, Dragon, Mauritius, Encounter and Jupiter were also at Singapore, but were under repair and not ready to sail. Japanese preparations Churchill publicly announced Prince of Wales and Repulse were being sent to Singapore to deter the Japanese. In response, Admiral Isoroku Yamamoto sent 36 Mitsubishi G4M bombers to reinforce the existing Mitsubishi G3M-equipped Kanoya Air Group and Genzan Air Group, whose pilots began training for an attack on the two capital ships. The bomber crews, of the Kanoya Air Group of Kanoya Kōkūtai (751 Ku), Genzan Air Group of Genzan Kōkūtai (753 Ku), and the Mihoro Air Group of Mihoro Kōkūtai (701 Ku), trained in torpedo attacks at an altitude of less than 10 metres (30 ft), and in long-range over-ocean navigation, so they could attack naval targets moving quickly at sea. Genzan Air Group was commanded by Lt Cdr Niichi Nakanishi, Kanoya Air Group by Lt Cdr Shichizo Miyauchi and Mihoro Air Group by Lt Hachiro Shoji. This was the first time in the war that a force of bombers was especially trained and equipped for “ship killing”, an unprecedented capacity, as around that time ordinary land-based bombers (particularly the Mediterranean theatre) had attacked ships at sea with limited success. Hostilities commence On 8 December 1941, early in the morning, bombers of Mihoro Air Group attacked Singapore. Prince of Wales and Repulse responded with anti-aircraft fire; no planes were shot down, and the ships sustained no damage. The Japanese made landings on Kota Bharu, Malaya, on 8 December (local time), commencing the Japanese invasion of Malaya. News arrived that Pearl Harbor had been attacked and eight US battleships had been sunk or disabled. Pre-war planning had explored the possibility of the United States Pacific Fleet sending major units to Singapore to reinforce the British when war broke out. That was now impossible. Phillips had concluded in an earlier discussion with US General Douglas MacArthur and Admiral Thomas C. Hart that his two capital ships were insufficient to confront the Japanese. However, with the Japanese threatening to overrun Malaya, Phillips was pressed to use his ships in an offensive role; he assembled his flotilla to