There it is.
A blogger (Reditt) posted a message the day of the bombing (Monday) that said the event was staged. Said - in advance - the perp would be an older teen or 20 year old. The raid to catch him would be held on Friday. The goal was to tax and regulate gun powder (no powder for ammo = no guns).
I'll try to find the original FR thread with a copy.
So, we were literally bombed by our own government?
I knew that was coming a few hours afterwards when the admin reps started sprinkling “low order explosive”, “smokless black powder” (idiots) and “smokeless powder” phrases in the press conferences.