Two people are dead after a shooting on the campus of the University of North Carolina at Charlotte, according to Mecklenburg Emergency Medical Service Agency.
Two other people are being treated for life-threatening injuries, and two more people have non-life threatening injuries, the agency said.
One person is in custody, a city official said.
Law enforcement officers were sweeping the affected buildings, the university tweeted.
“Follow officer commands,” the school said.
Video posted to twitter by Jordan Pearce, a student, showed people fleeing a campus library as police sprinted toward the building.
An image posted by Pearce shows a door where the glass is all over the floor inside a building.
The university, which has 30,000 students, tweeted: “Campus lockdown continues. Remain in a safe location. Monitor email and UNCC homepage.
Tuesday was the last day of classes, with exams to begin on Thursday.
Charlotte-Mecklenburg police are assisting university police in the case.
Developing story — More to come
By Dave Alsup and Dianne Gallagher, CNN