BB guns can cause serious bodily injury and may result in death. By legal standards, lethal force can be used.

I have to wonder why the boy had this bb gun and at a playground? I further question how he obtained said bb gun as that most place you need to be 18 or older to purchase one. Who obtained the bb gun, was it stolen ect? Where are the parents ect?

This was a tragic incident for all involved, that could have been averted but again, where the deceased had some responsibility in his own death.