It wouldn't be a great stretch to imagine that the local jihadis have captured M-4's or M-16's with which to fire 5.56mm ammo.
I wonder if a postmortem was even performed on the shootees due to the muslim insistance on planting the body in the ground asap.
This whole damn thing is smelling fishy -even moreso now that it's come up that the muz reporter that "broke" the story has a history of being detained by the US military.
It appears that Marines stayed with the bodies until a second group of Marines came to take them away. The second group was the ones who took the pictures, on the instructions of their superiors. So the bodies were not planted in the ground ASAP.
One of the things about the "altruistic" left is that they never pass up a chance to get even with somebody for a personal slight, especially is they can smear the entire brethren and get a few of them killed in the bargain.
They think they're clever. They're really just savages.