Pacific. Borneo also stood on the main sea routes between Java, Sumatra, Malaya and Celebes. Control of these routes were vital to securing the territory. Order of Battle Allied Defence in Sarawak and North Borneo The main objectives were the oilfields at Miri in Sarawak region and Seria in Brunei. The oil was refined at Lutong near Miri. Despite rich oil supplies, the Sarawak region had no air or sea forces to defend it. Only in late 1940 did Air Chief Marshal Sir Robert Brooke-Popham order the 2nd Battalion, 15th Punjab Regiment, a heavy 152 mm (6 in) gun battery from the Hong Kong-Singapore Royal Artillery, and a detachment of the 35th Fortress Company (Royal Engineers) to be positioned at Kuching. They numbered about 1,050 men. In addition, the Brooke White Rajah government also organised the Sarawak Rangers. This force consisted of 1,515 men who were primarily Iban and Dayak tribesmen. Altogether these forces were commanded by British Lieutenant Colonel C.M. Lane and was known as "SARFOR" (Sarawak Force). After having heard of the attack on Pearl Harbor, on 8 December 1941, the Brooke government ordered that the oilfields at Miri and Seria and refinery at Lutong be quickly demolished. Defence in Singkawang and Pontianak (Dutch East Indies) The Dutch forces had an important airfield near the border of British Malaysia (Sarawak) called "Singkawang II", which was defended by about 750 Dutch troops. On 25 November, five Brewster 339 Buffalo fighter planes arrived for local defence, followed in the beginning of December by Martin B-10 bombers. The Dutch Naval Aviation Group GVT-1, with three Dornier Do 24K flying boats, was located in Pontianak along with a KNIL garrison, commanded by Lieutenant Colonel Dominicus Mars, numbering approximately 500 men. Dutch forces in West Borneo consisted of the following units: West Borneo KNIL Garrison Battalion Stadswacht Infantry Company (about 125 men) in Pontianak Anti-Aircraft Battery (two guns) plus some AA machine-guns Mobile Auxiliary First Aid Platoon Stadswacht Detachment (about 50 men) in Singkawang Stadswacht Detachment (unknown strength) in Sintang Imperial Japanese The main Japanese force—led by Major General Kiyotake Kawaguchi—consisted of units from Canton, southern China: 35th Infantry Brigade Headquarters 124th Infantry Regiment from Japanese 18th Division 2nd Yokosuka Naval Landing Force 4th Naval Construction Unit 1 platoon of the 12th Engineer Regiment 1 unit from the 18th Division Signal Unit 1 unit from the 18th Division Medical Unit 4th Field Hospital,