Military police officers with the 850th Military Police Battalion from the Arizona National Guard escort role-play prisoners in a simulated flood evacuation at the Perryville Prison during Vigilant Guard here, Nov. 3. The scenario was a mock flood that took place at the prison and the role-play prisoners were evacuated to a secured location outside the facility with the assistance of the National Guard. Vigilant Guard is a three-day exercise, which evaluates military and civilian agency cooperation and communication in a time of disaster.