Neighbors say the house was overcrowded, but the city says no official complaints about the home or its landlord were ever filed.
"The only calls we've ever gotten from that property were garbage and debris calls," said Newark Mayor Ras Baraka.
Investigators said the fire started just hours after a birthday party when the young victims, ages 6 and 8, were playing with fire.
The Essex County Prosecutors Office has not yet released the identities of the two girls.
Neighbors said they are sadly and unfortunately, not surprised a tragedy happened there, and said that they had complained to the city about the tenants many times before.
"Many times. If it wasn't about the people, it was about the garbage, about the parties," said Newark resident Dalisa Anthony. "I even called the mayor's office one time. I tried to see what we could get done, and no one ever showed up."
Linwood Duncan lived on the third floor. He said that far too many people were living on the second floor and he had complained to the rental company handling the property for the owners.
"In the apartment on the second floor, there had to be about 20 people...at least 20," Duncan said. "They started bringing in these immigrants. I told myself, they've got mattresses in the hallway and they're living on the porch."
"You have shift work going on in apartments. Day shift covers the kids, and the night shift covers the kids at night, and you seven to 12 families living there, mattresses being stacked," said community activist Tony Agosto.
Neighbors watched tenants run from the house as the fire quickly spread, leaving the home next door heavily damaged as well.
Investigators were back at the house briefly on Monday, along with a firefighter, who says he worked the fire but came back as a citizen to remember the children who died.
"Everybody tried their best to help. It's not a good feeling," the firefighter said.
According to the city, since 2019, they recorded 34 calls about the property, but they say all the calls were concerning garbage and overgrowth on the property.
In light of the tragedy, the mayor said he's urging anyone who knows of a life-threatening situation at any property or home, to call 911.
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