Lost off Kurile Islands
On 27 May, Runner departed Midway for the Kuriles on her third patrol. She was never heard from again. Apparently, her torpedoes were functioning properly on this patrol, since post-war analysis of Japanese records indicated that the Seinan Maru was sunk off Hokkaido on 11 June, and the Shinryu Maru off the Kuriles on 26 June. Both sinkings were in Runnerâ€™s patrol area. The records are silent as to any action that might have resulted in her loss. Since there were four known minefields in her area, her loss is presumed to be due to striking a mine.