I thought I posted this but the manager of that plant says there's lots of that Ammonium Nitrate at the plant. He also said there was a report of a fire there, but the assumption being it caused a reaction with the nitrate thus the huge explosion.
It's horrible, but not a terrorist attack. Unless there's SOMETHING ELSE we don't know about but it does not sound like anything nefarious. Obama's gonna ban Ammonium nitrate
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