(Olympia, WA) -- Flags across Washington will be flown at half-staff today to honor Army Staff Sergeant Matthew McClintock, who was killed last month in the line of duty. McClintock, who was from Des Moines, was a Green Beret on his third tour of duty. He died January 5th in the Helmand Province in southern Afghanistan. Governor Inslee has ordered flags at all state government buildings to be flown today at half-staff.