(Reuters) - Four members of the North Carolina Air National Guard were killed and two critically injured in Sunday's crash of a military aircraft battling a wildfire in South Dakota, a U.S. brigadier general said on Tuesday.
The U.S. Air Force grounded for one day its fleet of firefighting tanker aircraft after the crash of the C-130 tanker, but the fleet was returned to service on Tuesday, the military said.
The number of dead and injured from the crash had not been confirmed by the military before Tuesday.
The injured airmen remained hospitalized and in serious condition on Tuesday, North Carolina Air National Guard spokesman Lieutenant Colonel Robert Carver said. Their names were not released.
"There are no words to adequately say how this has affected all of us who knew these airmen and their families," said Brigadier General Tony McMillan, commander of the North Carolina Air National Guard's 145th Airlift Wing based in Charlotte.
Those killed were Lieutenant Colonel Paul Mikeal and Major Joseph McCormick, both pilots; Major Ryan David, a navigator; and Senior Master Sergeant Robert Cannon, a flight engineer, McMillan said.
The plane was one of eight the U.S. Air Force has that can be quickly converted into firefighting tankers for a Defense Department-U.S. Forest Service program when private and commercial fleets cannot meet the need.
The investigation of the crash is ongoing, officials said.
The C-130 that crashed had been sent to support efforts to contain the White Draw Fire, which started on Friday afternoon about five miles northeast of Edgemont, South Dakota.
The fire had consumed about 4,950 acres and was about 50 percent contained as of Monday evening.
(Reporting by David Bailey in Minneapolis and Phil Stewart in Washington; Editing by Greg McCune and Will Dunham)