An AH-64 Apache attack helicopter flies above as U.S. Marines learn how to mark improvised explosive devices on Camp Leatherneck in Afghanistan's Helmand province, Dec. 20, 2013. An AH-64 Apache attack helicopter flies above as U.S. Marines learn how to mark improvised explosive devices on Camp Leatherneck in Afghanistan's Helmand province, Dec. 20, 2013. SHARE: Download: Full Size (2.62 MB) Tags: Photo Essays Credit: VIRIN: 064903-Q-JQP07-234.jpg Photo Gallery