Defense Department Can’t Confirm How Many ISIS Fighters Have Been Killed

EXCERPT:

COOK: "This is a war zone. This is a conflict. Much of our efforts are being conducted from the air, we don't necessarily have the ability to assess everything on the ground in the way we might like. And so, there have been a variety of -- of estimates, I know the Iraqis have had some estimates as well. And so, I -- I -- there isn't a good number for us to -- to share with you because we don't have great confidence in that number."