Maj. Gen. Harold Greene, a two-star U.S. Army general who held three advanced USC degrees, was killed in Afghanistan in an insider attack on Aug. 5. Greene, a native of upstate New York, was 55 years old.“Our thoughts and prayers are with Maj. Gen. Harold J. Greene’s family, and the families of our soldiers who were injured today in the tragic events that took place in Afghanistan,” said Army Chief of Staff Ray Odierno in a letter of condolence on the U.S. Department of Defense website.U.S. Maj. Gen. Harold Greene, right, was killed in an insider attack during his first combat deployment to Afghanistan. | Public domain photo courtesy of Matthew Hickman, U.S. ArmyThe Taliban claimed responsibility for the attack, in which a gunman wearing an Afghan army uniform opened fire on Americans and other Afghans at Camp Qargha, a military academy 11 miles west of the Afghanistan capital of Kabul, according to ABC News.Greene served in the U.S. military for 34 years. He is the highest ranked U.S. military officer killed in combat since 1970.Greene was the deputy for acquisition and systems management for the Office of the Assistant Secretary of the Army. His first combat deployment was to Afghanistan in January, where he served as a deputy commander in charge of training Afghan soldiers.The general’s awards included the Legion of Merit with three oak leaf clusters, the Meritorious Service Medal with a silver cluster, the Army Commendation Medal with three oak leaf clusters, the Army Achievement Medal and the Army Superior Unit Award.Several officials said Greene displayed leadership throughout his career. During a 2009 ceremony, Lt. Gen. Stephen M. Speakes, the U.S. Army deputy chief of staff, said, “When you look at a leader like [Greene] what you’re looking at is somebody who has that singular ability to display wisdom, and wisdom is a combination of a great background, a great sense of self, a sense of humility, and the ability to work extraordinarily hard, and [Greene] has all those qualities in ample profusion and proliferation.”Greene graduated from the Rensselaer Polytechnic Institute in Troy, N.Y. in 1980. He went on to receive a master’s degree in engineering, a master’s degree in science and a Ph.D. in materials science from USC.Greene is survived by his wife Sue Meyers and daughter Amelia.