NEW YORK (NewsNation Now) — Dozens were still hospitalized Monday after smoke from a fire knocked them out or trapped them in their apartments in a New York City high-rise building, the city’s deadliest fire in three decades. Seventeen people, including eight children, died in the blaze.

It was originally reported that 19 people, including nine children had died. Those numbers were updated on Monday.

As many as 13 people were in critical condition after Sunday’s fire in the Bronx. Investigators determined that a malfunctioning electric space heater, plugged in to give extra heat on a cold morning, started the fire in the 19-story building.

The flames damaged only a small part of the building, but smoke escaped through the apartment’s open door and turned stairwells — the only method of flight in a building too tall for fire escapes — into dark, ash-choked horrors.

Some people could not escape because of the volume of smoke, said Fire Commissioner Daniel Nigro. Others became incapacitated as they tried to get out. Firefighters found victims on every floor, many in cardiac and respiratory arrest, said Nigro.

Limp children were seen being given oxygen after they were carried out. Some who fled had faces covered in soot.

Fire Commissioner Daniel Nigro said an investigation was underway to determine how the fire spread and whether anything could have been done to prevent or contain the blaze.

The building is equipped with smoke alarms, but several residents said they initially ignored them because alarms were so common in the 120-unit building.

Large, new apartment buildings in the city are required to have sprinkler systems and interior doors that swing shut automatically to contain smoke and deprive fires of oxygen, but those rules don’t apply to thousands of the city’s older buildings.

Building resident Sandra Clayton grabbed her dog Mocha and ran for her life when she saw the hallway fill with smoke and heard people screaming, “Get out! Get out!”

Clayton, 61, said she groped her way down a darkened stairway, clutching Mocha. The smoke was so black she couldn’t see, but she could hear neighbors wailing and crying nearby.

“I just ran down the steps as much as I could but people was falling all over me, screaming,” Clayton recounted from a hospital where she was treated for smoke inhalation.

In the commotion, her dog slipped from her grasp and was later found dead in the stairwell.

The fire was New York City’s deadliest since 1990, when 87 people died in an arson at the Happy Land social club, also in the Bronx. The borough was also home to a deadly apartment building fire in 2017 that killed 13 people and a 2007 fire, also started by a space heater, that killed nine.

The fire in the Bronx comes just days after a large fire tore through a converted rowhouse in Philadelphia, killing 12 people, including eight children. The Associated Press reported the fire was the deadliest single fire in Philadelphia in at least a century.

The Associated Press and NewsNation affiliate WPIX contributed to this report.

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