>>10199858 Digg: Beirut and Ammonium Nitrate ~ The compound has to be mixed with something in order to be explosive
No it doesn't. Mixing it with a fuel that can utilize the oxygen released by the decomposing AN can greatly improve the explosive's power. But this is NOT necessary for AN to detonate.
This has happened many times before:
https://en.wikipedia.org/wiki/Ammonium_nitrate_disaster