About 2,750 tons of improperly stored ammonium nitrate ignited Tuesday in Lebanon’s capital in an explosion that devastated Beirut. In a matter of seconds, the blast at Beirut’s port toppled buildings, killed more than 150 people, injured thousands and left an estimated 300,000 residents homeless. Windows miles from the site of the explosion shattered. The city’s governor estimated the losses in the range of $10 billion to $15 billion.