WALTHAM (CBS) — A fire destroyed a four-unit home on Russell Street in Waltham Sunday.

Orlando Osorio, who lives on the first floor, says his neighbors upstairs alerted him to the fire.

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“They came, the rushed, they knocked on us, and when we opened it was just like a big dust cloud,” he told WBZ-TV.

The unit house about 20 people, all of whom are now displaced. No one was hurt.

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The Red Cross was on the scene helping residents find temporary shelter.

The cause of the fire is under investigation.

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