Four children, along with their mother and her step-brother, died when flames ripped through their home early Wednesday.
A vigil was held Thursday at PS 194, where the children attended school.
Parents, teachers and friends set up candles and balloons and wrote condolences and memories on posters with pictures of the victims. Grief counselors were also available for students.
The fire broke out around 1:45 a.m. in the kitchen of the fifth-floor apartment inside the Frederick Samuel Houses on Adam Clayton Powell Boulevard.
Investigators released a picture of a burned pot on a stove, which firefighters say was left unattended and started the tragic fire.
Authorities were also investigating if the smoke and carbon monoxide detector -- which had been successfully tested in January -- was wrapped in towel to prevent it from going off while cooking.
Video footage from the fire apartment at 2441 7th Avenue in Harlem, where two adults and four children were killed early this morning. pic.twitter.com/TBAR5i5ri4— FDNY (@FDNY) May 8, 2019
Two adults, a 45-year-old Andrea Pollidore and her step-brother 33-year-old Mac Abdularaulph, were killed, along with her four children, identified as 11-year-old Nakiyra, 8-year-old Andre, 6-year-old Brooklyn, and 3-year-old Ellijah.
They were all pronounced dead at the scene.
Investigators also learned Pollidore was seriously injured in a kitchen fire at her previous home on Jefferson Avenue in Bedford-Stuyvesant, Brooklyn, during which she sustained first-degree burns and memory loss.
She was briefly in a coma before recovering, and careless cooking was believed to be the cause.
"It's unbelievable to me, I'm just stuck," said Pollidore's surviving daughter, Raven Reyes, who came home early Wednesday morning to learn of the tragedy.
"It's unbearable, it's indescribable, it's just like, I don't even have words," she said.
The building is a city-run housing authority complex.
This is the deadliest fire in New York City since the December 2017 fire in the Bronx that killed 13 people.
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