The U.S. Navy has dismissed the commander of the 7th Fleet, which is based in Japan. A series of Navy ship accidents raised concerns about Vice Admiral Joseph Aucoin's ability to command operations in the Pacific. Aucoin took command of the 7th Fleet in September 2015 and was expected to retire in a few weeks. A statement from the Navy said Rear Admiral Phillip Sawyer will replace Aucoin. Sawyer, who had already been named as Aucoin’s successor, will take command immediately. There have been four Navy accidents in the Pacific since late January, including two collisions that left sailors dead and missing. Admiral Scott Swift is the commander of the US Pacific Fleet. “While each of these four incidents is unique, they cannot be viewed in isolation,” Swift said earlier. Most recently, on Monday the Navy ship USS John S. McCain collided with a ship carrying oil near Singapore. The crash injured five sailors and left ten others missing.