The fire broke out at about 4 p.m. on the 1700 block of Surf Avenue, according to the Monmouth County Prosecutor's Office.
The woman's name had not been released.
An investigation into the cause and origin of the fire, involving members of the Prosecutor’s Office and the Monmouth County Fire Marshal’s Office, is ongoing.
There has been no indication of any foul play being involved, the prosecutor said.
Multiple fire departments responded from surrounding towns to assist the Belmar Fire Department including: Spring Lake, Wall, Ocean, Neptune, Sea Girt, Asbury Park, Avon, and the Monmouth County Fire Marshal.
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