NEW YORK (WABC) -- The horrific apartment building fire in the Bronx that killed 13 people is now becoming a teachable moment about fire safety.
Fire officials say the mother of the 3-year-old boy who started the fire didn't close the door to her burning apartment as she left, and that allowed the fire to spread -- fast.
So the FDNY is urging the public to close the door on their way out. Watch Marcus Solis' story in the player above.
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