BELMONT, Bronx -- The NYPD says that a 13th person has died from their injuries sustained in the Belmont, Bronx, apartment building fire one week ago.
27-year-old Holt Francis was critically injured, but died at the hospital on Thursday.
It's the worst fire tragedy in NYC in at least a quarter of a century. The victims killed were eight adults and five children -- ranging in age from 1 to 63. Three people remain in critical condition.
RELATED: What we know about the Bronx fire victims
The fire was apparently caused by a 3-year-old boy playing with the stove.
The boy's mother was alerted to the fire by the boy screaming. She escaped the apartment with her kids but left the front door open.
FDNY Commissioner Nigro said this caused the fire to spread to the rest of the building very quickly by traveling up the stairs. It acted like a chimney and people in the rest of the building had very little time to react.
Mayor Bill de Blasio called it a "horrible, tragic accident."
PHOTOS from the scene:
"Children starting fires is not rare," Nigro said, adding that the city has a program to educate the public about fire safety. He said that if there is a lesson to be learned from this tragedy is that if you have an apartment fire you must close the front door.
"We're told the boy had a history of playing with the burners and turning them on, and before the mother knew it, this fire had gotten a good hold in the kitchen," Nigro said. "She said it was a lot of fire, a lot of smoke, grabbed the children and ran out."
She failed to close the door behind her and so the fire, hungry for oxygen, raged right through, pouring down the hallways and turning the central staircase into a chimney of death.
"Based on research we have right now, it does not appear anything problematic with the building or the fire safety in the building," the mayor said on WNYC radio. "Just a fire that spread very very quickly, and took so many lives."
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13th person dies one week after Bronx fire
BELMONT BRONX DEADLY FIRE
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