ELMWOOD PARK, N.J. (CBSNewYork) — Investigators said Wednesday that an electrical appliance may be to blame for a fatal fire at a multi-family home in Bergen County.

The blaze broke out around 11:30 p.m. Tuesday at a house on Miller Avenue in Elmwood Park.

When first responders arrived, police said the house was fully engulfed in flames with thick smoke pouring from the building.

Tony Ambrogio said the homeowner, his sister-in-law, heard smoke alarms and escaped her first floor apartment.

“She ran over to here to our neighbor. By that time, the house was engulfed in flames,” he said.

It took firefighters from four neighboring towns 30 minutes to bring the fire under control. Inside the home, investigators found a body of a woman who lived alone in the upstairs apartment, CBS2’s Magdalena Doris reported.

“She just got trapped in the fire and she died,” Ambrogio said. “Fairly young woman. It’s really tragic.”

The victim’s identity has not yet been released.

The cause of the blaze is still under investigation, but according to Elmwood Park Fire Chief Michael Pressler, preliminary evidence is pointing towards the fire starting in the kitchen possibly due to an electrical appliance.

There was also a partial roof collapse of the building.

The Bergen County Prosecutor’s arson investigation unit is also investigating.