By CBS3 Staff

UPPER MACUNGIE, Pa. (CBS) — Two firefighters are recovering after a three-alarm fire tore through a senior living center in Lehigh County Sunday morning. Dozens of elderly people were rushed outside to safety and now crews are searching for a cause.

Flames shot into the sky at Heather Glen Senior Living in Upper Macugie near Allentown around 3 a.m. Sunday.

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Dozens of firefighters battled the blaze, while others rushed to the more than 80 people who live here to help them outside.

“The most important thing was the safety of the residents at the facility,” Fogelsville Volunteer Fire Company Chief, Jacque Creamer said..

One woman had to be rescued from her window and helped onto a ladder.

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“Because of the conditions we had inside the facility yes there were some individuals who were removed from windows and down ladders,” said Chief Creamer.

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Officials believe the fire started in the exterior of the building and spread up into the roof. But, investigators are still working to figure out what caused it.

What we do know is that six residents and two firefighters were taken to a nearby hospital with minor injuries. They’re expected to be OK.

The condition of the building is another story.

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“It did some extensive damage,” Chief Creamer said.

Now nearby senior living facilities like South Mountain Memory Care in Emmaus are stepping in, allowing some of the 80-plus displaced residents to live there for time being.

Heather Glen Senior Living will be closed during repairs to the facility. So far there is no word how long that could take.

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CBS3’s Matt Petrillo contributed to this report.