OAKLAND (CBS SF) – An elderly woman was found dead in a fire that destroyed an extensively renovated and expanded home in the Oakland hills Monday night, a fire battalion chief said Tuesday.

The fire was reported at about 11 p.m. at 3221 Hood St. near the Oakland Zoo. The home was about 1,200 square feet when it was built but had been renovated and expanded to cover 2,000 square feet, Battalion Chief Coy Justice said.

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The home was engulfed in flames when firefighters arrived. The odd layout made fighting the fire difficult since the additions gave the house many oddities and hidden spaces for fire to spread, Justice said.

Twenty firefighters fought the blaze inside for 30 minutes before getting out of the house and fighting it defensively.

While outside, they still had trouble controlling the blaze and finally realized there was a gas leak feeding the flames. Once they got the gas shut off, they managed to control the fire, but at that point the home had been burning for more than an hour and was destroyed, Justice said.

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Once the fire was out, firefighters found an elderly woman’s body inside. She is believed to be a resident of the home, but it wasn’t immediately clear if she owned it. Justice said he doesn’t know if anyone else lived there.

The Alameda County coroner’s bureau has so far been unable to identify the woman’s badly burned body and will likely have to use dental records.

The cause of the fire and whether the renovations were up to city code remains under investigation. One firefighter fell off a ladder while fighting the blaze and was taken to a hospital with injuries not considered life-threatening.

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