Military police are the trained police maintained by a nation's armed forces. On military installations, these men and women have powers similar to those of civilian police. Military police enforce military laws and regulations, control traffic, prevent and investigate crime, apprehend military absentees, maintain custody of military prisoners, and provide physical security for military personnel and property. In combat situations, military police also maintain custody of prisoners of war. When necessary in combat, military police can be ordered to fight as infantry.