Fire crews responded to a two-story house on Westwood Drive just before 5 a.m. after reports of a fire.
According to police, three female residents were transported to Cooperman Barnabas Medical Center in Livingston.
One of them, identified as 36-year-old Chinwe Obi, was pronounced dead. Her mother and sister are being treated for smoke inhalation.
The cause remains under investigation.
Anyone with information is encouraged to contact the Essex County Prosecutor's Office Tips Line at 1-877-TIPS-4EC or 1-877-847-7432.
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