According to UNC News Services, an "anonymous person" called 911 about a man and a gun.
A Carolina Alert was sent out shortly before 9 a.m. warning that the university was on lockdown. The university also activated sirens on campus.
Emergency: The University has activated the sirens. Police report an ARMED AND DANGEROUS PERSON ON OR NEAR CAMPUS. https://t.co/NvQ5A3xrAJ— UNC Public Safety (@UNCDPS) December 2, 2015
The lockdown was lifted around 9:15 a.m. after the area around the ROTC building at 221 South Columbia Street was searched.
A photo on Twitter showed law enforcement had the intersection at South Columbia Street and McCauley Street blocked.