NEW YORK (CBSNewYork) -- A family of six, including four children, lost their lives in a fire early Wednesday morning in Harlem.
The tragedy may have been caused by missing batteries in a smoke detector. NYCHA says the building's smoke detectors were last inspected in January, and found to be working properly.
Flames broke out around 1:40 a.m. inside apartment 5G at the Frederick Samuel Houses on Adam Clayton Powell Jr. Boulevard and 142nd Street.
The FDNY released video of the aftermath of the inferno in the apartment. Another video taken by a neighbor shows a firefighter facing down massive flames that stood between rescuers and the six family members who perished inside.
"Units were met at the door of that apartment with fire. The entire apartment was involved," FDNY Commissioner Daniel Nigro told reporters. "(Firefighters) aggressively moved in, extinguishing the fire. As they did, when they reached the two rear bedrooms, we found six occupants of that apartment deceased."
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Authorities identified the victims as 45-year-old mother Andrea Pollidore, four children under the age of 11, and her 32-year-old stepson. Three other residents suffered minor smoke inhalation.
"We're in the business of saving lives, and in this instance we were not able to, and it's very difficult for our members to deal with this loss also. But right now our hearts are with these poor people and their friends and family," said Nigro.
Raven Reyes, the family's 27-year-old daughter who lives elsewhere, spoke about the loss of nearly her entire family.
"I really just can't believe this happened," she said. "I just want them to know I love them so much."
Reyes lost her mom, stepbrother, and four young siblings. The oldest of whom was 11, the youngest only 3 years old.
"My brothers and sisters, even my step-brother passed away. They were all good people," she said. "My little brothers and sisters, they just were perfect. Amazing. They were amazing, no matter what the circumstances, you know."
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Mayor Bill de Blasio called the family's death a "gut-wrenching moment for all of us."
"As a father, just thinking about, you know, yesterday evening four children went to bed and they're gone now. It's very, very painful," de Blasio said during a midday news conference. "We obviously need to know everything that happened with it, but most importantly, our hearts and our prayers need to be with this family."
Jean Belot, the father of the youngest victim Elijah, showed CBS2's Dave Carlin a father-and-son moment caught on video.
"He was smart and a quick learner and that's all, and that's pretty much all I have to say for now," he said.
Neighbor Patricia Flowers, who lives on the same floor as the family, told Carlin she last spoke with the kids as they were on their way outside with their bicycles.
"The kids was really vibrant and happy kids. I was just with them yesterday, and they are very good kids and the mom, she took very good care of her kids," she said.
Nigro said it appears the fire started on the stove, and there's no indication that it was suspicious. The kitchen is located near the front door, and the commissioner said the layout of the apartment left the victims with nowhere to run.
"The fire escapes from this apartment are on the side of that apartment opposite from the bedrooms. So, they were unable to get to either the door of their apartment or the windows that are on the fire escape." he said.
"If there was a fire, there you would be walking into the fire if you were trying to get through the front door," said building tenant Claudette Grant.
The building is owned by the New York City Housing Authority. Interim Chair Kathryn Garcia said a combination smoke alarm-carbon monoxide detector was installed in the unit in June 2017 and tested this January.
FDNY Investigating If Smoke Detectors Worked In NYCHA Apartment Where Family Died In Blaze
Sources say it's possible it may have been tampered with. The FDNY is investigating whether the mother or anyone else removed the batteries.
"If she disconnected the smoke detector - we don't know that yet - and a NYCHA worker was in the apartment and didn't report the smoke detector not working, then NYCHA bares some of the blame for what happened," said Mark Peters, CBS2's urban affairs expert.
A candlelight vigil honoring the victims was held at 7 p.m.
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