PHILADELPHIA (AP) -- Police say a pizza deliveryman shot and wounded by plainclothes officers may have mistaken them for robbers. Two city police officers responding to a report of gunshots shortly before 10 p.m. Tuesday in the Kingsessing neighborhood saw a man walking down the street wearing a dark shirt with the hood pulled up and his hands in his pockets and tried to stop him, police said. Philadelphia police Deputy Commissioner Richard Ross said the man fled to a car and then drove toward the officers, who fired because they feared for their safety. "They believe they're being run over, and they fire their weapons," Ross told WCAU-TV. "We believe, unfortunately, that he also is of the belief that he is being robbed." Ross said "it looks like it could just be a totally unfortunate situation." The man may not have heard the officers identify themselves, Ross said. "I don't know if he thought they were fake police officers or he just didn't hear what they were saying," he said. Authorities said the 20-year-old resident of nearby Upper Darby was in critical condition at the Hospital of the University of Pennsylvania with gunshot wounds to the head, neck and leg. Detectives and the police department's internal affairs unit were investigating. The two officers have been assigned desk duty, which is standard procedure, Ross said.