UPDATE: A fire that killed a 77-year-old Montvale widow in her home last weekend was ignited by a discarded cigarette, authorities said Friday.
The blaze that tore through the North Avenue home of Ninette Grannis broke out just before 1 p.m. Sunday.
"When the Montvale Police and Fire Departments arrived on the scene, the single-family residence was consumed by heavy fire," Acting Bergen County Prosecutor Dennis Calo said Friday.
Grannis "was unaccounted for and presumed to be inside," he said.
Her remains were later located, Calo said.
"The cause of the fire was determined to be accidental due to carelessly discarded smoking materials," the prosecutor said.
Calo's Arson Investigations Unit investigated, along with the Bergen County Sheriff's Bureau of Criminal Identification, which collected evidence.
Several fire departments assisted, including Park Ridge and Woodcliff Lake.
Several EMS units also responded.
Ninette (Starets) Grannis's husband of 52 years, U.S. Marine Corps veteran Grosvenor Grannis III, was 76 when he died at their home in 2014.
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