PITTSBURGH (AP) _ A sniper fired 20 random shots from an apartment-house rooftop Friday and held off police, who blocked off streets in the area and evacuated two schools near the University of Pittsburgh campus.

No injuries were reported in the stand-off.

Residents saw the sniper, wearing an orange hunting cap, sitting on the edge of the 15th-story roof with his legs dangling over the edge.

Police sharpshooters took up positions on rooftops nearby, radio station KQV reported.

About 50 police officers were on the scene.

Students at the grade school and high school at nearby St. Paul's Cathedral were evacuated.