Firefighters respond after an explosion and building collapse in the East Harlem neighborhood of New York, Wednesday, March 12, 2014. The explosion leveled an apartment building, and sent flames and billowing black smoke above the skyline.

John Minchillo / AP

Firefighters respond after an explosion and building collapse in the East Harlem neighborhood of New York, Wednesday, March 12, 2014. The explosion leveled an apartment building, and sent flames and billowing black smoke above the skyline.