So far, the use of robots in military operations is mostly limited to exploring and transportation missions, but that seems to be changing soon.The robot called “Modular Advanced Armed Robotic System” (in short MAARS) is in safety testing phase which will also have mounted weapons. Please see original article here. Apart from being lethal, the robot also possesses many non lethal forms of weapons, such as sending out laser pulse, shooting out smoke or beam bags.
Compared to just a few years ago, the overall robot use in combat has increased significantly. Today there are thousands of ground robots and unmanned aerial vehicles are in use in Iraq and Afghanistan. The actual war fighting, decision making robots are still in early phases of development but this will eventually be a big part of the military as well. This will bring up new ethical issues too of course.