Rescuers were called to a three-story industrial warehouse at 2nd and Wharton streets in South Philadelphia around 2:15 p.m.
That warehouse is used by the Fralinger String Band to store equipment, Action News has learned.
The view from Cell 6 showed a large plume of black smoke rising over the block.
Early reports indicate at least one person was taken to the hospital to be treated for smoke inhalation.
