A documentary Video on YouTube discribes about a clssified operation during Iraq war American Army used three Swords Robots(armed unmanned ground vehicle (UGV) system).
SWORDS Armed Robot in Iraq
The Special Weapons Observation Remote Direct-Action System (SWORDS) capability is in theater. The SWORDS robot represents a new technological concept currently in the developmental stage. Three robots have been built so far; and while there has been considerable interest in fielding the system, some technical issues still remain and SWORDS is not currently funded. The U.S. Army’s 3rd Infantry Division has used the robots for surveillance and peacekeeping/guard operations. The robot is armed with Squad Automatic Weapon (SAW), M249 Light Machine Gun, and has not yet been used with this weapon in combat.