The Bethlehem Fire Marshal’s office has completed investigation of the May 2 fire at 510 E. Third St.; the luxury apartments called Five 10 Flats.

They determined that the fire originated on an outdoor patio/deck on the roof of the building. The fire extended into the sixth-floor elevator lobby and consumed a large portion of the roof before it could be extinguished. The fire was caused by improperly discarded smoking materials.

This corroborates what was reportedly said by building owner Peron Development’s John Callahan. He told members of the media rooftop security showed a resident placing a cigarette butt into a flower pot which then began to smolder.

Fire Investigators from the Fire Marshal’s office will work with fire investigators representing the involved insurance companies as their investigation progresses, said Deputy Chief Craig Baer in a statement. The American Red Cross and the building ownership are working with the building tenants to provide support and services as needed.