Abston says the man is described as a 6-foot white man with a long brown coat.
Also locked down were Riley Hospital for Children on the campus and a nearby Crispus Attacks High School, a medical magnet school.
IU School of Medicine lab technician Kamakshi Sishtla says she hunkered down in a small, windowless equipment room. The building where she works is across the street from where the gunman was spotted.
Classes resumed Monday after spring break.