A worker at a Downtown steam plant who brought a pellet rifle to work to shoot pigeons was mistaken for a sniper Wednesday afternoon, prompting police to shut down part of the city for about two hours. Richard Wills, of Dawson, Fayette County, a maintenance worker in the Pittsburgh Allegheny County Thermal building, brought the weapon to work to chase pigeons away from broken windows on the building's roof, said PACT President Robert Fazio. Someone apparently spotted him - and his rifle - when he stepped out onto the roof for a few seconds, Fazio said. At least three witnesses...