Some physics experts say fertilizer explosions are some of the worst blasts there are.  Dr. Michio Kaku, a well known physics professor at the City University of New York explains how the blast in West, Texas may have been triggered. 

Kaku calls it a rare sequence of events but tells "CBS This Morning"  the right temperature, amount of water and pressure will set off anhydrous ammonia.  Yesterday's massive explosion leveled entire sections of the town of West, injured more than 160 people and left an unknown number dead.