fighter, the CAC Boomerang. RAAF Kittyhawks came to play a crucial role in the New Guinea and Solomon Islands campaigns, especially in operations like the Battle of Milne Bay. As a response to a possible Japanese chemical warfare threat the RAAF imported hundreds of thousands of chemical weapons into Australia. In the Battle of the Bismarck Sea, imported Bristol Beaufighters proved to be highly effective ground attack and maritime strike aircraft. Beaufighters were later made locally by the DAP from 1944. Although it was much bigger than Japanese fighters, the Beaufighter had the speed to outrun them. The RAAF operated a number of Consolidated PBY Catalina as long-range bombers and scouts. The RAAF's heavy bomber force was predominantly made up of 287 B-24 Liberators, equipping seven squadrons, which could bomb Japanese targets as far away as Borneo and the Philippines from airfields in Australia and New Guinea. By late 1945, the RAAF had received or ordered about 500 P-51 Mustangs, for fighter/ground attack purposes. The Commonwealth Aircraft Corporation initially assembled US-made Mustangs, but later manufactured most of those used. By mid-1945, the RAAF's main operational formation in the Pacific, the First Tactical Air Force (1st TAF), consisted of over 21,000 personnel, while the RAAF as a whole consisted of about 50 squadrons and 6,000 aircraft, of which over 3,000 were operational. The 1st TAF's final campaigns were fought in support of Australian ground forces in Borneo, but had the war continued some of its personnel and equipment would likely have been allocated to the invasion of the Japanese mainland, along with some of the RAAF bomber squadrons in Europe, which were to be grouped together with British and Canadian squadrons as part of the proposed Tiger Force. However, the war was brought to a sudden end by the US nuclear attacks on Japan. The RAAF's casualties in the Pacific were around 2,000 killed, wounded or captured. By the time the war ended, a total of 216,900 men and women served in the RAAF, of whom 10,562 were killed in action; a total of 76 squadrons were formed. With over 152,000 personnel operating nearly 6,000 aircraft it was the world's fourth-largest air force. Cold War Postwar During the Berlin Airlift, in 1948–49, the RAAF Squadron Berlin Air Lift aided the international effort to fly in supplies to the stricken city; two RAF Avro York aircraft were also crewed by RAAF personnel.