"Therefore what are we talking about here? Has gun then kill? "
Obviously. "Go there and kill anyone you see".
That's the level of orders you can give to AI: Pick humans from ground and shoot at them.
Differentiating between humans? Probably not possible, and as everyone is an enemy anyway, not necessary.
Oh, wrong group of people? Too bad, make sure to kill all so no wittnessess and no recordings.