Avenger class ships are designed as mine sweepers/hunter-killers capable of finding, classifying and destroying moored and bottom mines. These ships 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. The ships are of fiberglass sheathed, wooden hull construction.
Guardian ran aground on Tubbataha Reef about 70 nautical miles (130 kilometres) south east of Palawan in the Philippines on the 17th of January, 2013. The U.S. Navy evacuated all 79 crew members from the minesweeper on the following day. On the 19th of January, an assessment team was deployed to plan and execute the vessel's extraction. It was intended for Guardian to be removed from the area by crane ships from Singapore and then be placed on a barge or other ship, since the ship was too damaged to be towed due to multiple hull penetrations. On the 29th of January, the United States Navy announced that the ship would be cut into three sections on the reef prior to removal, resulting in the total loss of the ship. USS Guardian was decommissioned and struck from the Naval Vessel Register on the 15th of February, 2013.