I'm going to cut them some slack and consider that it took them a couple minutes to realize what was going on and respond. A lot can happen in a couple minutes with a gun, a crowded theater, and chaos.
I don't know much about hiow fast someone can shoot whatever kind of gun he was using, but if it took the LE even one minute to respond, I wouldn't rule out the possibility of several deaths and injuries.
But I'm sure if you had been there, it would have ended differently, wouldn't it?
Your sarcasm noted. No, it would not have ended differently for I am not a policeman.