Fire fighters battled a stubborn three-alarm fire for two hours in a Center City apartment building last night before bringing it under control.

The dramatic blaze, at 1025 Spruce St., was reported at 9:04 p.m. in the four-story building, which is owned by Phi Chi Housing Inc., a medical fraternity that provides housing for Thomas Jefferson Medical College students. By the time the third alarm was sounded, flames could be seen shooting out of the upper floors of the masonry structure.

By 10 p.m., officials were concerned about people watching the fire from neighboring rooftops, and medics were being summoned to the scene. Initial reports were that three firefighters suffered minor injuries.

It was not immediately clear what started the blaze. Fire fighters late last night were still at the scene dousing hot spots.

- Kathleen Brady Shea