 United States Navy minesweepers commenced operations in Brunei Bay on 7 June , and a flotilla of four cruisers and seven destroyers ( including an Australian light cruiser and destroyer ) served as a covering force . The minesweeping operation was successful , though USS Salute struck a mine on 8 June and sank with the loss of four lives . Underwater demolition teams investigated all of the landing beaches on 9 June searching for obstacles which could impede the landing craft . The teams assigned to clear obstacles off Labuan were endangered by an unauthorised attack on the island conducted by a force of American B @-@ 24 Liberator heavy bombers . Following the landings on 10 June , American Thirteenth Air Force aircraft flying from a base on Palawan Island in the Philippines provided close air support for the forces on Labuan until RAAF units based on the island were ready to take over . 
