The University of North Carolina at Chapel Hill has issued an "all clear" less than an hour after sending an emergency alert about an armed and dangerous person.
The school activated its emergency sirens Sunday afternoon. Authorities also had locked the doors to Carmichael Arena, site of an NCAA women's tournament game between the Tar Heels and the University of Tennessee at Martin.
Chapel Hill police say the armed man was in custody.
Students and others on campus had been advised to close their windows and doors and stay inside while the alert was in effect.
The school says the sirens are activated when there's an emergency or safety threat to the campus.