I'm not proud of my thoughts, and I'm not proud of the hundred or so sarcastic remarks that I've thought of since I first heard the news either.
I am genuinely saddened that this happened, and my most sincere hope is that whomever did so is apprehended quickly and that nobody else is injured or killed while that happens. At the same time, the explosion looks (at least to me) like Tannerite, and I'm also thinking that perhaps Tannerite is going to get banned, or regulated, despite being, basically, iron oxide; which would make such a ban pretty futile.