US officials have said the Navy is to dismiss Vice Adm Joseph Aucoin as commander of the Seventh Fleet following a string of collisions involving warships in Asia. Ten sailors are still missing after the USS John S McCain collided with an oil tanker near Singapore on Monday. <br/><br/>The crash was the fourth such incident in a year. The Seventh Fleet, based in Yokosuka, Japan, is the largest forward-deployed fleet in the US Navy, with some 50 to 70 vessels and submarines. Vice Adm Aucoin, who has been its commander since 2015, was due to retire within weeks. <br/><br/>His removal is the latest in a series of steps taken by navy officials after the USS John S McCain collision. It is not clear when a formal announcement will be made.