CHAPEL HILL, N.C. (WNCN) — Sirens rang out as students and staff were urged to once again hide and seek shelter at UNC-Chapel Hill’s campus Wednesday afternoon.

An emergency alert regarding an armed and dangerous person on or near UNC Chapel Hill’s campus went out on Wednesday at 12:54 p.m. This scare came two weeks and two days after the fatal shooting of Associate Professor Dr. Zijie Yan inside the Caudill Labs building on campus.

Chapel Hill police announced the arrest of 27-year-old Mickel Deonte Harris of Durham in connection to an incident that triggered the lockdown. Harris, police said, already had an arrest warrant out for him for an assault on Sept. 5.

According to a statement from Chancellor Kevin Guskiewicz, the alert was activated following reports of a person pulling out a gun inside the Student Union. UNC Police reported no shots were fired, and the situation was related to a “personnel matter.”

“Following the incident on Monday, Aug. 28, the news of another armed person and a second lockdown on our campus is concerning and can be traumatic,” Guskiewicz said. “I am grateful to our UNC Police and Emergency Operations team for managing this situation quickly and efficiently. Thank you to our faculty, staff and students for their cooperation and patience as we continue to strive to keep our community safe.”

An all-clear was issued on the university’s campus after more than an hour since the initial alert. On Wednesday afternoon, UNC-Chapel Hill officials announced that classes are canceled for the rest of the day and non-mandatory operations are suspended. All classes will resume as scheduled on Thursday.

Chapel Hill-Carrboro City Schools have sent out an all-clear for their schools after being under a “secure mode” lockdown. School officials say dismissal times are normal, but bus services could be delayed.

In the fatal shooting on the school’s campus on Aug. 28, police arrested Tailei Qi, a UNC-Chapel Hill student, without force off campus less than two hours after the shooting.

Qi was charged with first-degree murder and a weapons count and is in jail without bond.

The shooting and nearly three-hour lockdown terrified students and faculty. On Tuesday, North Carolina college students, many of whom attend UNC-Chapel Hill, rallied outside the General Assembly pushing for stricter gun laws.