SACRAMENTO (CBS13) – An early morning fire in Sacramento’s Mansion Flats neighborhood could have been worse had it not been for an observant passerby, firefighters say.

The incident started around 2:30 a.m. Thursday in a three-story Victorian building at 15th and F streets.

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One person and several pets were rescued from the home.

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Crews say the fire could have been a lot worse had it not been for a passing driver, who saw the flames and called 911.

Crews say they were able to contain flames to the first floor.

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Exactly what caused the fire is under investigation.