The fire broke out at a three-story building on the 3100 block of Charlotte Avenue in Palmer Township on Monday afternoon.
The Palmer Municipal Fire Department worked with several local crews to locate and douse the blaze, which was upgraded to a third alarm from a first alarm, authorities said.
Assisting agencies include Suburban EMS, the Nancy Run Fire Company, and fire departments in Wilson Borough, Williams Township, Bethlehem Township, Hanover Township, Nazareth, Upper Nazareth, Lower Nazareth, Forks, and East Allen.
The cause of the fire remained under investigation by the Palmer Municipal Fire Department.
Scroll down to view additional photos from the scene.
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