The fire broke out on Norwood Terrace around 5 p.m. A person inside was pulled from the home and was later pronounced dead at an area hospital.
Pictures on social media show large piles of clothing and other household items obstructing an entrance to the home. News 12 New Jersey quoted firefighters who said a hoarding situation made fighting the fire more difficult.
The Millburn Fire Department referred questions to the Essex County Prosecutor's Office, which had no additional information as of Thursday morning.
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