Gas explosion at NY apartment injures 9, including 2 kids in critical

NEW YORK, NY -- A gas explosion Thursday at an apartment in New York City has left nine people injured, including two children who are in critical condition, police and fire sources said.

Six out of the nine injured are children, police told ABC News. The youngest is a 5-year-old with special needs.

The blast occurred on the second floor of an apartment in the Bronx, blowing the front door off the home and into a tree. Most walls were blow out, too, authorities said.