The building is located at 184 Pendale Drive.
That's in Greenfield Township, Blair County.
The call went out around 11 o'clock Tuesday night.
Crews were on scene for a couple hours as they worked to get the fire under control.
Everyone was evacuated from the building.
We're told one fire fighter was injured and treated at the scene.
There were no reports of other injuries.
The Red Cross is assisting the families who lived there.
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