During April and May 1944, the 380th engaged in the most intensive and sustained operations since arrival in the southwest Pacific, neutralizing the rear bases through which the Japanese might reinforce their air force in the Wakde-Hollandia area of the Netherlands East Indies. From the end of May 1944 until it moved to Murtha Field, San Jose, Mindoro, Philippines in February 1945, the 380th concentrated on neutralizing enemy bases, installations and industrial compounds in the southern and central East Indies. In April 1945, Far East Air Forces relieved the 380th of its ground support commitments in the Philippines. During the month, the Group flew the first heavy bomber strikes against targets in China and French Indochina. In June 1945, the 380th was placed under the operational control of the 13th Air Force for pre-invasion attacks against Labuan and on the oil refineries at Balikpapan in Borneo. For nearly two weeks, the Group's Liberators kept these targets under a state of aerial siege. After the Borneo raids, the 380th flew its last combat missions to Taiwan.