SHERMAN OAKS (CBS) — Fire investigators Saturday were expected to pick through the ruins of a home that went up in flames just before the family’s planned Armenian Christmas celebration.

The fire at the 5,500-square-foot, two-story home on N. Matija Avenue broke out around 7:09 p.m. Friday and burned for about an hour before it was put out, said Matt Spence of the Los Angeles Fire Department.

It was unclear how many people were in the home at the time the fire started.

Homeowner Art Satanyan told the Sherman Oaks Patch that he was watching TV when a fire alarm went off and he saw the family’s 20-foot Christmas tree ablaze.

It took nearly 60 firefighters to put out the fire, which eventually spread to the second-floor of the home and attic.

One firefighter was taken to a local hospital with minor injuries, Spence said. No other injuries were reported.

A damage estimate was not immediately available. The exact cause of the fire has yet to be determined.

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