By JENNIFER PELTZ and DAVID JEANS
Associated Press

NEW YORK (AP) - A preschooler toying with the burners on his mother's stove accidentally sparked New York City's deadliest fire in decades, an inferno that quickly overtook an apartment building and blocked the main escape route, the fire commissioner said Friday.

A dozen people died , and four others were fighting for their lives a day after the flames broke out in the century-old building near the Bronx Zoo.

The 3½-year-old-boy, his mother and another child were able to flee their first-floor apartment. But they left the apartment door open behind them, and it acted like a chimney that drew smoke and flames into a stairwell. From there, the fire spread throughout the five-story building, authorities said.

The city housing department said investigators would look into why the door did not close automatically, though Mayor Bill de Blasio said there was "nothing problematic about the building that contributed to this tragedy."

At least 20 people scrambled out via fire escapes on a bitterly cold night, but others could not.

"People had very little time to react," Fire Commissioner Daniel Nigro said. Firefighters arrived in just over three minutes and saved some people, but "this loss is unprecedented."

Fernando Batiz said his 56-year-old sister, Maria Batiz, and her 8-month-old granddaughter also died, though the baby's mother survived.

"The smoke, I guess, overcame her. Everything happened so quick," Batiz said. He described his sister, a home care attendant, as a selfless person who helped him when he was homeless.

"I don't know what to think. I'm still in shock," he said.

One family lost four members: Karen Stewart-Francis, her daughters, 2-year-old Kiley Francis and 7-year-old Kelly Francis, and their cousin, 19-year-old Shawntay Young, relatives said. Stewart-Francis' husband, Holt Francis, was hospitalized, the family said.

"I don't know what to do, and I don't know how to feel," Stewart-Francis' mother, Ambrozia Stewart, told The New York Times. "Four at one time - what do I do?"

Young lived in the basement but had gone upstairs to visit Stewart-Francis in her fifth-floor apartment, said Young's boyfriend, Kenyon George.

"The first story I heard is that she was up top and she couldn't get down," said George, 19, fighting back tears. The two had dated for seven months, and Young had become a mother figure to his 1-year-old son, he said. She called him Thursday morning, but he was asleep and missed the call.

"If I had picked up the phone, she would have been over here all day," he told The Associated Press. "It feels so surreal."

The 26-unit apartment building was required to have self-closing doors, which swing shut on their own to keep fires from spreading, city Housing Preservation and Development Department spokesman Matthew Creegan said. Investigators will look at whether the door to the apartment was defective or if an obstruction prevented it from closing, he said.

No self-closing door violations were issued during an inspection in August, though the city would not have examined every apartment, Creegan said. Such violations are common: The city cited 7,752 of them last year.

While the doors are required in any apartment building with more than three units, they sometimes do not work properly because they get clogged or dirty, New York fire-safety consultant Jim Bullock said.

The management company for the building's owner, D&E Equities, said it was talking to city officials and was "shocked and saddened" by the deaths and injuries.

Excluding 9/11, Thursday's fire was the city's deadliest since 87 people were killed at a social club in the same Bronx neighborhood in 1990. A fire in a home in another part of the Bronx killed 10 people, including nine children, in 2007.

About 170 firefighters worked in 15-degree weather to rescue dozens of people. Fire Department video released Friday showed the building's charred halls and stairs, where icicles had formed from water poured on the blaze.

Residents described opening their front doors to see smoke too thick to walk through and descending icy fire escapes with children in hand. Some escaped barefoot or in their nightclothes.

Huddled in a deli on the block with her family, 10-year-old Crisbel Martinez cried Friday as she recalled escaping from her fifth-floor apartment with her three older brothers.

One brother's girlfriend was coming into the building when she saw smoke, called him and called police. With their mother at work, the siblings checked and saw the smoke.

"Then we got changed and went through the fire escape," Crisbel said. She spent the night at an aunt's house.

Twum Bredu still did not know Friday what had become of his brother, Emmanuel Mensah, 28. He was staying with a family that escaped the fire safely, but no one could find Mensah, despite checking four hospitals. Still, his family pounded the pavement, asking about him and hoping for good news.

"That's my prayer," Bredu said.

The building was too old to be required to have modern fireproofing such as sprinkler systems and interior steel construction.

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Associated Press Writer Larry Neumeister contributed to this report.

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