US Navy Minesweeper Runs Aground on Reef in the Philippines U.S. Navy A U.S. Navy minesweeper has run aground on a reef in the Sulu Sea in the Philippines. The ship remains stuck on the reef. No injuries were reported among the ship's crew of 81 and there were no indications of a fuel leak. A Navy statement said the USS Guardian (MCM-5) ran aground on the Tubataha Reef at 2:25 a.m. local time while transiting in the Sulu Sea. The reef is located almost 400 miles south of the Philippine capital of Manila. According to the statement released by the Navy's Seventh Fleet, the Avenger-Class mine countermeasures ship was en route to its next port of call when the grounding occurred in the middle of the Sulu Sea. "The ship is currently stuck on the reef, approximately 80 miles east-southeast of Palawan Island," said the statement late Wednesday. The crew is currently working to determine the best method of safely extracting the ship. A Navy official said the grounding is under investigation. An initial damage assessment did not find any leakage of fuel or oil from the ship. The ship's crew of 81 included six officers and 75 enlisted sailors. The USS Guardian is based in Sasebo, Japan. According to a Navy fact sheet, the Navy's 14 Avenger-Class ships "are designed as mine sweepers/hunter-killers capable of finding, classifying and destroying moored and bottom mines." With hulls made of wood and sheathed in fiberglass, the 224-foot-long vessels "use sonar and video systems, cable cutters and a mine detonating device that can be released and detonated by remote control. They are also capable of conventional sweeping measures. A number of the vessels have been deployed to the Persian Gulf over the past year to counter any possible Iranian threat to close the Strait of Hormuz with mines.