A man and woman were hurt when a two-story building collapsed late Thursday night on North Front Street next to the Market-Frankford El tracks in North Philadelphia, police said.

Shortly before 10 p.m., police and firefighters responded to the 2200 block of North Front Street and found three adjacent addresses filled with rubble, said Chief Inspector Scott Small.

A woman, believed to be 68, and a man, believed to be 69, were transported to Temple University Hospital, where they were listed in stable condition. The man and woman were in a second-floor apartment when the collapse occurred.

Small said that a total of three neighboring two-story buildings collapsed and two of them may have been vacant.

Google Street View imagery from September 2019 shows that the middle address was an empty lot.

Small said that Market-Franford El tracks were not affected, but train service in the immediate area was suspended as a precaution.

City inspectors and utility workers also responded to the scene.

Tha cause of the collapse was under investigation.