NEW YORK (CBSNewYork) — Officials late Wednesday were investigating a fire that claimed the lives of two young children.

A mother collapsed trying to reach the children while they were trapped inside the burning apartment building, at 1368 Webster Ave. in the Butler Houses public housing development.

Investigators said she was across the street when the fire broke out.

Two sisters — Amanda Jabie, 18 months old, and Jannubi Jabie, 2 — were killed, and several adults were also hospitalized, in the fire, officials said.

The all-hands fire broke out around 6:45 p.m. on the third floor of the 21-story building, officials said.

As CBS2’s Dave Carlin reported, the children were surrounded by flames and thick smoke, unable to escape.

Neighbor Daven Jackson said he ran to the apartment’s door, but the situation was too hot, visibility was zero, and he had to retreat.

“We heard kids crying, but it was too black and we couldn’t breathe,” Jackson said.

The family in the apartment next door put wet towels under the door and waited to be rescued by firefighters.

“I open the door to a bunch of black smoke, I closed the door back,” Tisha Dozier said.

Witnesses said they don’t believe any adults were in the apartment at the time, and said they saw a woman running out of a laundromat across Webster Avenue yelling that her kids were trapped inside.

The two kids were said to be unconscious in the arms of firefighters when they were taken from the building.

“I seen the firemen bring the kids out and they were burnt all over their body,” David Lawson said.

The two children had been rushed to Bronx-Lebanon Hospital Center where they were later pronounced dead, officials said. Nine adults were also treated for smoke inhalation, and other minor injuries.

Investigators also said when the girls’ mother came to the scene, she went into shock and fainted and had to be hospitalized.

FDNY Deputy Chief Gary Rocco said the fire marshal was looking at whether the children were unattended in a home that may have been without safeguards.

“Checking to see if there are smoke detectors in the apartment and preliminarily we did not see any smoke detectors,” Rocco said.

The cause was under investigation late Wednesday.

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