May 6, 1942 the USS Luzon PG-47 was scuttled in Manila Bay. The Luzon was one of 8 small river gunboats built for the US Navy by Kiangnan Dock & Engineering Works in Shanghai for duty on the Yangtze River. She was launched on Sept. 12, 1927 and commissioned on June 1, 1928 and was the flagship of the Yangtze River Patrol.

After the Japanese invasion of China the Luzon fell back again and again until she left China for the Philippines arriving at Manila on Dec. 30, 1941. As the Japanese advanced the Luzon was scuttled to avoid capture. The Japanese however, refloated her and renamed her Karatsu. They used her until May 3, 1944 when the USS Narwhal SS-167 torpedoed and damaged her. She was towed to Manila and scuttled in Feb. 1945.