Flames started just after 11 a.m. Saturday at the home on Liberty Street in West Orange.
Fire officials found two kids, both under the age of 10, unconscious inside the home. An adult was also found unconscious. Paramedics performed CPR, but they all died.
Neighbors say the adult who died was the grandmother of the two children. They say they were concerned about the family because police were often called to the house.
One neighbor who lives across the street tells Eyewitness News they had no idea there was a fire, but they all heard the boys' mother screaming when she returned home on Saturday morning.
"Daughter was going crazy - she was hysterical. All the kids are dead, and you can see them give compressions. The mother was the last one to come out, and finally they put screens up," said the neighbor.
The exact cause of death is still under investigation. The names of the children have not been released.
The cause of the fire is also under investigation.
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