On the Ground Military police officers train by using an on the ground based operational surveillance system, a multispectral sensor and persistent surveillance system, at U.S. Army Yuma Proving Ground, Ariz., April 8, 2025. SHARE: Download: Full Size (1.82 MB) Tags: Border Support Credit: Mark Schauer, Army VIRIN: 250408-A-GD561-5112K.JPG Photo Gallery