At 3:30 a.m., firefighters were on scene at 69 Mercer St., Passaic County Prosecutor Camelia Valdes, Paterson Police Department Officer In Charge Isa Abbassi, and Paterson Fire Chief Alex Alicea said.
Firefighters discovered the body on the second floor of the house after putting out the blaze, authorities said. The identity of the deceased has not been confirmed, authorities said.
Paterson Mayor Andre Sayegh said the city is in mourning.
"Our firefighters worked feverishly to contain the fire and prevented any further loss of life," Sayegh said.
The investigation is active and ongoing and anyone with information is asked to contact 1-877-370-PCPO.
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