The North Carolina National Guard has released the names of the C-130 crewmembers who were killed when their MAFFS air tanker crashed in South Dakota on Sunday.

Dead are Lt. Col. Paul K. Mikeal, 42, of Mooresville, N.C.; Maj. Joseph M. McCormick, 36, of Belmont, N.C.; Maj. Ryan S. David, 35, of Boone, N.C.; Senior Master Sgt. Robert S. Cannon, 50, of Charlotte.

“Words can’t express how much we feel the loss of these airmen,” said Brig. Gen. Tony McMillan, 145 AW commander. “Our prayers are with their families, as well as our injured brothers as they recover.”

Mikeal was assigned to the 156th Airlift Squadron as an evaluator pilot and had more than 20 years of service. He leaves behind a wife and two children.

McCormick was an instructor pilot and chief of training for the 156th Airlift Squadron. He was married with four children.

David was an experienced navigator and was also assigned to the 156th. He joined the North Carolina Air National Guard in 2011 after prior service in the active-duty U.S. Air Force. He is survived by his wife and one child.

Cannon had more than 29 years with the Charlotte unit and was a flight engineer with the 145th Operations Support Flight. He was married with two children.

The names of the injured will not be released. Both of the injured airmen remain hospitalized.

The crew and its aircraft along with two other 145th C-130s and three dozen airmen flew from Charlotte to Peterson Air Force Base in Colorado Springs, Colo., Saturday to assist with fighting forest fires in the Rocky Mountain region. They were due to move to a base in Cheyenne, Wyoming on Monday. The crash occurred around 6:30 p.m. MT near Edgemont, South Dakota as the crew was dropping retardant on the White Draw fire. The cause of the crash is unknown and is under investigation.