The workers were atop the roof when the blaze broke out at 524 W. Broad St. in West Bethlehem around 7:15 p.m., LehighValleyLive reports citing fire chief Warren Achey.
It was not initially clear if the roof work was connected to the cause of the fire, Achey said.
“It sounds like there was some work going on on the roof, we don’t know if that’s the cause of it yet,” he told the outlet.
“But there was work going on on the roof. The firefighters rescued three people off the top of the roof.”
Three buildings on the west side of the blaze were evacuated as well, authorities said.
The fire was doused within about an hour, and no injuries were reported, Achey said.
The Nancy Run Fire Co. and Bethlehem police and EMS also assisted at the scene.
The fire remained under investigation, authorities said.
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