[Mashiro]

I'm a bit late to reply to all previous messages. Yes, ammonium nitrate in itself is not directly an explosive chemical substance. Under the right conditions it can however explode in a very aggressive and fueled combustion. We probably have reached the stage at which it was changing its structure due to wrong storage and handing. And that additional fire of whatever it was (actually don't matter if it were fireworks because any fire source could have caused it) of course helped a lot. I did a bit of research. With the wrong conditions ammonium nitrate will deteriorate and its substance will change. With the heat coming from the fire the process has been accelerated and the ammonium nitrate in effect fueled the fire and caused a massive combustion releasing a lot of power. In fact with heat and pressure through destillation chemists turn ammonium nitrate into the base component of explosives called nitric acid.

Today while driving on my way to work I listened to some news regarding this from a local radio station "Cosmo". According to their sources the government has been warned about this issues and dangers about some months ago (I think they said two and a half). And they did nothing as can be seen. Experts told them about the dangers and problems with the storage conditions.

A lot has gone wrong in this case but most importantly it seems that the government knew about this early enough and decided to do nothing.