That's a disgusting and unnecessary outcome. Understood that the cops will be amped up, even the inevitability of having to return fire when fired upon... But there's no excuse for the mass unloading and extreme lack of fire discipline. If they had to shoot, fine, but understanding that there could be hostages, and many other bystanders around by default, this response is just murderous.
These people have no idea what the heck they're doing. They shouldn't be carrying guns.
RIP brother. I hope something can be learned or changed from your loss.