Authorities are urging people at Northwestern University in suburban Chicago to take shelter after a report of a gunman and shots fired in a student residential building.
In a Twitter post, Evanston police say there was a report of a gun and "shots fired" but that officers had not found "evidence of a victim, scene or gunman."
University spokesman Jon Yates says the report comes from Engelhart Hall, a graduate student dormitory. But he says the university has not confirmed that any shots were fired.
The university also sent a tweet asking people to stay away from the area and to "shelter in a safe place and stay until further notice."
The report comes as students across the country walked out of school to protest gun violence.
