active thermitic material discovered in dust from the 9/11 world trade center catastrophe http : //www.benthamscience.com/open/tocpj/articles/v002/7tocpj.htm ? tocpj/2009/00000002/00000001/7tocpj.sgm [ 87 ] on 21 september 2001 , two explosions occurred in the outskirts of toulouse , france , destroying the azf fertilizer factory and the secret snpe rocket fuel factory .