It’s being reported that the bomber wanted to buy ammonium nitrate:

Joel tried to purchase ammonium nitrate at a feed store late last week.

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FEED STORE MANAGER TALKS TO REPORTERS ABOUT HINRICHS VIDEO HERE

Domestic manufacture of ammonium nitrate was halted earlier this year. It is going to be much less of an issue in future events of this sort. The price for it is is going to much higher than other forms of fertilizer that perform the same function in the field. Anyone that asks for it is going to be immediately identifying themselves as a non-typical user. The ATF and the fertilizer industry have been working together to reduce the chances that someone is going to misuse it. And as others of have noted the use of the alternative TATP will result in more Darwin awards and fewer innocents being injuried.

This is not to say I’m happy about the availablity of AN decreasing. I’m of the opinion that the misuse of the AN could and should have been prevented through less drastic means other than discontinuing the manufacture of the product. That our stadium bomber was asked what he was going to use it for and was unable to give a straight answer, which put the store manager on alert, proves the less drastic solution worked in this case.