This is why people get over scared about things like this. Do you know what it was? Do you know why it was "seriously hazardous" other than it's flammable? Come on. Flammable, yes. Hazardous, not really unless a huge amount explodes. To be considered "seriously hazardous" it will have to have the potential to be extremely harmful to people/living things without going through some reaction first. Just saying.
Either way, this shit is nuts and would have been a hell of a sight to see.