Updated

The highest-ranking U.S. military officer to be killed in combat since Vietnam has been buried with full military honors at Arlington National Cemetery.

Maj. Gen. Harold J. Greene, a two-star general, was killed last week when a gunman believed to be an Afghan soldier opened fire at a military academy near Kabul.

A riderless horse accompanied the caisson that carried Greene's flag-draped casket to his gravesite on Thursday afternoon. Greene's son, First Lt. Matthew Greene, clenched the hands of his mother and sister and handed his mother a tissue as soldiers folded the flag that had covered the casket and a military band played "America the Beautiful."

U.S. Army Chief of Staff Gen. Ray Odierno presented flags to Greene's widow, his son and daughter and his father.