WASHINGTON — The U.S. soldier fatally wounded in a hostage rescue mission in Iraq heroically inserted himself into a firefight, Defense Secretary Ash Carter said Friday.

Carter applauded Army Master Sgt. Joshua L. Wheeler, 39, of Roland, Okla., who died of his wounds Thursday.

The defense chief gave the most extensive public description yet of what transpired in the raid on an Islamic State prison. About 70 people were freed. It was the first time U.S. troops took part in direct ground combat in Iraq since the war against the Islamic State started.