— Chapel Hill police took a man into custody late Sunday afternoon following reports of "an armed and dangerous person" that briefly put the campus of the University of North Carolina at Chapel Hill on lockdown.

The UNC Department of Public Safety said police received reports around 4:20 p.m. of a man wielding a knife or knives near a campus courtyard known as The Pit in front of the Frank Porter Graham Student Union.

The man then took off north toward Franklin Street, where officers took him into custody about 45 minutes later in a church parking lot near the intersection of East Franklin Street and Raleigh Road.

UNC police have neither identified the man nor said whether he is affiliated with the university or why he might have been on campus.

Karlton Suits, an employee at Alpine Bagel Café, inside the Student Union, said he saw the man acting strangely and then arguing with a student before pull out two knives and screaming, "Get out."

Suits said the man then followed the student outside near The Pit to a dining hall, where two other people confronted him.

That's when, Suits said, the man took off.

Video showed police taking into custody a man with long brown or blond hair who appears to be in his 20s or early 30s. He was wearing a gray striped long-sleeve shirt and dark pants.

Chapel Hill police say they are also investigating whether a reported attack around 9:30 p.m. Saturday might be related.

In that case, UNC student Peter Diaz said the man sat next to him and a friend at the bar at Old Chicago Pizza & Taproom on West Franklin Street.

When they left, Diaz said, the man picked up his beer and darted out in front of them outside the restaurant and pulled out a switchblade.

"He flicked his switchblade and said, 'You better keep walking,'" Diaz said Sunday night. "We had never talked to this man, had no idea what happened."

Sunday's knife sighting prompted UNC to activate its Alert Carolina emergency system, which included notifying students, faculty and staff via text and email as well as activating sirens across campus.

Those on campus were advised to seek shelter immediately and close and lock doors and windows.

That alert was lifted shortly after 5:15 p.m.

In an email to the university community Sunday night, UNC Chancellor Carol Folt praised campus police for its quick response in notifying the university community.

"Today was a vivid reminder of the importance of preparation and following the instructions of our campus safety officials when we think there is a risk to our campus community," Folt said. "I appreciate the way all of you look out for each other's safety and welfare. We will always learn from these events in order to make Carolina as safe as it can be."