Security Halt Marine Corps Sgt. James Johnston scans the surrounding area during a convoy security halt on Joint Base Elmendorf-Richardson, Alaska, March 6, 2016. Johnston is assigned to Detachment Military Police Delta Company, 4th Law Enforcement Battalion. Air Force photo by Alejandro Pena SHARE: Download: Full Size (1.6 MB) Tags: 4th law enforcement battalion, marines, military police, urban operations training, joint base elmendorf-richardson Credit: Alejandro Pena VIRIN: 160306-F-YH552-011A.JPG Photo Gallery