The fire broke out around 3 a.m. Sunday at Heather Glen Senior Living facility in Upper Macungie Township outside Allentown. Flames raced up a rear wall and spread to the roof.
Firefighters used ladders to rescue at least a half-dozen residents.
Two firefighters were injured.
Upper Macungie Fire Chief Edgardo Colon says it took "a lot of creativity" to get everyone out safely.
The cause of the blaze remains under investigation.
The senior center's residents will have to live elsewhere while the building is repaired.
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