Investigators are examining why safety doors at Sunday's deadly apartment fire in the Bronx failed to close automatically as required by law, allowing choking smoke to fill the building and kill 17 people, including eight children, Mayor Eric Adams said on Monday.

The cause of the fire — New York City’s deadliest in nearly 32 years — was a malfunctioning electric space heater in a duplex unit spanning the second and third floors. Had that unit's door self-closed after the occupants fled, the blaze likely would have been contained, according to FDNY Commissioner Daniel Nigro.

Although the flames themselves were limited to that unit and an adjacent hallway, the death toll grew because the smoke spread through the building, a 19-story, 120-unit apartment in a housing development called Twin Parks North West in the borough's Tremont section.

Also contributing to the calamity: A stairway door on the 15th floor didn't close automatically as required by law, Nigro said, sending smoke continuing onward and upward.

"They are self-closing, but the door on 15, and the door to the fire apartment, was not functioning as it should," he said.

What to know

  • Investigators are examining why safety doors at Sunday's deadly apartment fire in the Bronx failed to close automatically as required by law, allowing choking smoke to fill the building and kill 17 people.
  • In the neighborhood Monday, residents of the building recalled a nightmarish morning, and those who lost loved ones lamented unbearable absence.
  • Kelly Magee, a spokeswoman for the group that owns the building, said that in July its maintenance staff fixed a lock on the front door of the duplex and at the same time checked the self-closing mechanism, and it was working. She said no problems were reported subsequently.

In the neighborhood Monday, residents of the building recalled a nightmarish morning a day earlier, and those who lost loved ones lamented unbearable absence.

Tijan Janneh was mourning one of his daughters, who was 24, while his younger daughter remained hospitalized.

"God gave [one] to us and God took her," Janneh, 61, said.

The youngest victim was 4 years old, said City Councilman Oswald Feliz.

Kelly Magee, a spokeswoman for the group that owns the building, said that in July its maintenance staff fixed a lock on the front door of the duplex and at the same time checked the self-closing mechanism, and it was working. She said no problems were reported subsequently, and that alarms in the building appeared to be working properly on Sunday.

She said the building code mandated sprinklers only in the trash compactor and laundry room because the building has floors and ceilings made of concrete.

Sprinklers might have saved lives, said Ronald Siarnicki, executive director of the National Fallen Firefighters Foundation.

"Most likely it would have extinguished that fire or at least held it in check and not produced the amount of toxic smoke," Siarnicki said. "Would I love to see every building with sprinklers in our country? Absolutely. But it's going to take time."

Adams said that investigators are looking into why the doors didn’t close, and whether the exit stairwells were properly lit.

"There may have been a maintenance issue with this door, and that is going to be part of the ongoing investigation," the mayor told "Good Morning America" earlier Monday.

He said the building owners told the city that the doors had self-closing mechanisms, in compliance with a 2018 city law requiring self-closing doors. That law was passed months following a fire, also at a Bronx apartment, in which 13 people were killed after a fleeing family left the door open, allowing flames to spread.

"At the heart of the problem was, really, the open door that allowed the smoke to move through. It wasn’t the fire that really consumed so many lives; it was the smoke," Adams told Fox 5 News on Monday. "And this is not to, you know, put any additional burden on the family in that apartment. It’s almost muscle memory that you flee an apartment, and sometimes you forget about closing the door."

City inspectors have issued violations for problems with self-closing doors on five apartments in the building and one opening to a stairwell stretching back a dozen years, according to a database maintained by the Department of Housing Preservation and Development. The records state that all the violations were corrected.

Speaking at the fire scene, Adams said Monday afternoon that the city medical examiner had revised the fire's death toll — to a total of 17, nine adults and eight children — instead of 19, as city leaders had reported earlier. The higher figure was due to a double count in tallying those taken to the seven hospitals where victims are being treated, said Nigro, who cautioned that critically injured patients remain hospitalized whose prognosis is uncertain.

"This number could, unfortunately, increase again," he said.

Fatima Wood, 30, who on Sunday was visiting her 6-year-old daughter, Dasanii, and her father inside a ninth-floor apartment unit, said: "We just thank God that we’re out here safely … not making funeral arrangements."

Hagi Tunkra, who lost five relatives in the blaze, said he's been crying and is unable to eat.

"It's terrible," he said.

Banu Simaha, a Bronx resident, said six people he knew died, including his brother’s wife and daughter. The deceased, like him, are from Gambia, a country in West Africa.

"They are my family," said Simaha, 64. "I pray to God for them. I feel so bad. I feel so bad."

The investigation is also looking into reports that past false alarms led some residents to ignore the alarm system as thick smoke billowed upward, Adams said.

"We’re going to look at that system and ensure that the alarm system didn’t repeatedly malfunction," Adams told CNN Monday morning about the fire.

Fifteen people remain hospitalized in critical condition, FDNY spokesman Frank Dwyer said Tuesday.

The entire building was vacated, with some occupants staying in hotels and others with family, said acting New York City Emergency Management Commissioner Christina Farrell.

The mayor on Monday added that President Joe Biden called to extend condolences and offer help.

On the freezing street outside the charred brick building Monday morning, even the pastors leading a community vigil had to hold back tears, pausing prayer to regain composure.

"We ask you to bring strength to each family member that is affected by this," said the Rev. Kevin McCall, a civil rights pastor, while down on one knee. "Bring strength to this community, each resident."

In tight embraces, attendees held one another. One woman cried. Many were on the verge of tears.

The building backdrop — broken windows, banged out by firefighters, or the residents themselves, to vent the thick smoke — was a bleak reminder of what happened Sunday.

Father Michael Kissane, of St. Simon of Stock and St. Joseph Catholic Church in the Bronx, said he understood the enormity of the fire "when they started bringing the bodies out."

"New Yorkers, people in time of tragedy come together," Kissane said. "We come together here of all different faiths in order to pray to one God."

Said NYPD Chaplain Robert Rice: "Unfortunately, we lost so many … and there’s families grieving."

The fire started just after 11 a.m. in a bedroom of the duplex unit. To maximize firefighting and rescue operations inside the building, FDNY personnel searching for survivors were "pushing the envelope" of the 45 minutes of air in self-contained breathing apparatuses they carry, said James McCarthy, president of the Uniformed Fire Officers Association labor union.

"They give you some escape time, 10 to 13 minutes, to get out. An alarm goes off, and it lets you know that their air is low, and you need to get out, but many of the firefighters in this incident operated while those alarms are going off and pushing the envelope as close as possible to running out of air, and some did, just to try and save as many lives as possible," McCarthy said, speaking at a Zoom news conference on Monday morning.

Adams said the city would seek to bring back a public-service campaign from past generations urging that those fleeing a fire close the door to contain the smoke and flames.

"If we take away one lesson from this, [it] is the closing of the door. It’s imperative. I remember as a child hearing that commercial and PSA over and over again, ‘close the door, close the door.’ We’re going to double down on that," he said.

Adams said the building’s heat was working Sunday.

"You know, sometimes people have additional warmth that they want in their apartments, and that is why they use space heaters from time to time," he said.

A fire department official said the space heater had been running for a "prolonged period."

With AP and Cecilia Dowd

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