In the Pacific theatre, American forces accompanied by the forces of the Philippine Commonwealth advanced in the Philippines, clearing Leyte by the end of April 1945. They landed on Luzon in January 1945 and recaptured Manila in March. Fighting continued on Luzon, Mindanao, and other islands of the Philippines until the end of the war. Meanwhile, the United States Army Air Forces launched a massive firebombing campaign of strategic cities in Japan in an effort to destroy Japanese war industry and civilian morale. A devastating bombing raid on Tokyo of 9–10 March was the deadliest conventional bombing raid in history. In May 1945, Australian troops landed in Borneo, overrunning the oilfields there. British, American, and Chinese forces defeated the Japanese in northern Burma in March, and the British pushed on to reach Rangoon by 3 May. Chinese forces started a counterattack in the Battle of West Hunan that occurred between 6 April and 7 June 1945. American naval and amphibious forces also moved towards Japan, taking Iwo Jima by March, and Okinawa by the end of June. At the same time, a naval blockade by submarines was strangling Japan's economy and drastically reducing its ability to supply overseas forces. On 11 July, Allied leaders met in Potsdam, Germany. They confirmed earlier agreements about Germany, and the American, British and Chinese governments reiterated the demand for unconditional surrender of Japan, specifically stating that "the alternative for Japan is prompt and utter destruction". During this conference, the United Kingdom held its general election, and Clement Attlee replaced Churchill as Prime Minister. The call for unconditional surrender was rejected by the Japanese government, which believed it would be capable of negotiating for more favourable surrender terms. In early August, the United States dropped atomic bombs on the Japanese cities of Hiroshima and Nagasaki. Between the two bombings, the Soviets, pursuant to the Yalta agreement, invaded Japanese-held Manchuria and quickly defeated the Kwantung Army, which was the largest Japanese fighting force. These two events persuaded previously adamant Imperial Army leaders to accept surrender terms. The Red Army also captured the southern part of Sakhalin Island and the Kuril Islands. On the night of 9–10 August 1945, Emperor Hirohito announced his decision to accept the terms demanded by the Allies in the Potsdam Declaration. On 15 August, the Emperor communicated this decision to the Japanese people through a speech broadcast on the radio ("Gyokuon-hōsō", literally