The Agar Place fire broke out in the rear of the 1½-story home shortly after 3 a.m. and instantly spread, responders and neighbors said.
An off-duty South Hackensack police sergeant who lives next door to the victims tried to extinguish the flames with a garden hose, but the blaze spread too quickly.
Firefighters had to beat back heavy flames and extreme heat, in fact, before finding 80-year-old homeowner Teresa Savino and Anton Pechal (Merkulov), 29.
Both of them were taken to Hackensack University Medical Center, where they were pronounced dead.
The homeowner's daughter, 44-year-old Giuseppina Savino, was hospitalized with smoke inhalation.
The fire ravaged the home, collapsing a floor and part of the roof. It was declared under control shortly before 4:30 a.m.
CPR efforts failed after both deceased victims were found in cardiac arrest.
Because fatalities were involved, the Bergen County Prosecutor's Arson Squad is investigating the cause, assisted by South Hackensack fire officials.
Mutual aid responders included firefighters from Carlstadt, Hackensack, Hasbrouck Heights, Little Ferry, Moonachie, Rochelle Park, Wallington and Wood-Ridge.
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