YORK, Pa. (AP) — Two firefighters have died and two others are injured after the partial collapse of a former piano factory in York, Pennsylvania.

York Mayor Michael Helfrich said in a statement Thursday that firefighters Ivan Flanscha and Zachary Anthony died after being transported to York Hospital. Helfrich said Assistant Chief Greg Altland and firefighter Erik Swanson were in stable condition and being treated for non-life-threatening injuries.

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York officials say part of the four-story building fell on the firefighters as they were looking for hot spots and investigating the cause of a fire that broke out Wednesday. The Weaver Organ and Piano factory was being converted into residential units.

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Officials have not released the names of the firefighters caught in the collapse.

York is about 100 miles (about 160 kilometers) west of Philadelphia.

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