Nine U.S. Air Force airmen formerly missing from the Vietnam War were buried as a group today at Arlington National Cemetery in Virginia, the Pentagon said.

On May 22, 1968, the men were aboard a C-130A Hercules cargo aircraft on a mission over northern Salavan Province, Laos. The crew of another U.S. aircraft observed a large ground fire near the last known location of the C-130.

Between 1989 and 2008, teams led by the Joint POW/MIA Accounting Command headquartered in Hawaii conducted 10 field investigations and four excavations in Quang Tri Province, Vietnam.

They recovered aircraft wreckage, human remains, crew-related equipment and personal effects, the Pentagon said.

Scientists from the accounting command and the Armed Forces DNA Identification Laboratory used mitochondrial DNA and dental comparisons to identify the remains, which were previously returned to families.

The U.S. Air Force members buried today were: Col. William H. Mason, Camden, Ark.; Lt. Col. Jerry L. Chambers, Muskogee, Okla.; Maj. William T. McPhail, Chattanooga, Tenn.; Maj. Thomas B. Mitchell,  Littleton, Colo.; Chief Master Sgt. John Q. Adam, Bethel, Kan.; Chief Master Sgt. Calvin C. Glover, Steubenville, Ohio; Chief Master Sgt. Thomas E. Knebel, Midway, Ark.; Chief Master Sgt. Melvin D. Rash, Yorktown, Va.; and Master Sgt. Gary Pate, Brooks, Ga.

 Since 1973, the remains of 927 Americans missing from the Vietnam War have been identified and returned to their families, the Pentagon said. A total of 1,719 service members remain missing from the conflict.