I wasn't sure what you were talking about specifically, but I guess this article confirms a bystander was hit:

Trib - Bystander struck by bullet in Downtown Pittsburgh, police say > A woman was grazed by a bullet in Downtown Pittsburgh Tuesday afternoon during a dispute between two men, police said. > >Police responded to the intersection of Smithfield Street and Fourth Avenue around 12:10 p.m. Officers found a woman with a gunshot wound to her lower leg. > >“The shooting occurred during a dispute between two individuals on Smithfield Street,” police said in a news release. “The shooting victim was not involved in the dispute, and was walking past.”

So many of these incidents seem to be stupid arguments between people and then they start shooting wildly.