The shooter who killed three people in a Cincinnati office high-rise once acted disoriented after being fired four years ago in South Carolina, and he filed a recent lawsuit that a judge in June said "borders on delusional." Authorities on Friday said they have not figured out why 29-year-old Omar Enrique Santa Perez opened fire inside the lobby of a building where he never worked or had any known connection.

The city's police chief said the gunman's mental health history is one of several areas they are investigating. Police Chief Eliot Isaac said Santa Perez bought the 9 mm handgun legally about a month ago in Cincinnati before he randomly shot at workers Thursday morning in the building that houses the headquarters of Fifth Third Bancorp.