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 and confronted a coworker inside the Student Union at Alpine Bagel.

Investigators say he had a gun but did not fire it. Harris ended up leaving in a vehicle and the arrest occurred off campus.  UNC Police reported no shots were fired, and the situation was related to a “personnel matter.”

Campus police continue to investigate the exact motive.

The lockdown alert went out nine minutes after UNC-Chapel Hill Police Chief Brian James said the 911 call came in. He said the lockdown was not instant because police had to first confirm the situation themselves.

“We certainly don’t ever want to send out an alert and it’s not warranted because when we have to send it out in a time when it’s critical people may not pay attention to it,” James said. “So we want people to be assured anytime that alert goes out for a lockdown, that people take it very seriously and act accordingly.”

CBS 17 asked Chief James why a photo or video of the suspect was not released to the public while police were looking for him. 

James said often times police are trying to pull footage simultaneously as the lockdown is happening. He said in this instance, by the time police were able to access the footage they had already confirmed the location of the suspect.

Some employees at UNC say they’re worried that there have been two shootings in 16 days.

“[I’m] definitely worried for my friends that are still here and the poor freshman. It’s their first year and they’ve already gone through two of these,” said John Shin, UNC employee and graduate. “It’s awful and no one should go through this.”

“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.”

During Wednesday’s press conference, Guskiewicz added, “we’ve got a lot of support for the students and faculty staff. I hope that they’ll access any resources that they may need as they process this. And as I’ve said we’re going to do everything possible to reassure everyone that visits this campus, lives, learns, works here, that this is a safe place to be.”

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.

UNC sophomore Sage Clausen is a member of March For Our Lives, the group at the General Assembly Tuesday, and said it was overwhelming to have a lockdown happen again. 

“Students here, along with community members across the state, are really fed up with the cycle of gun violence that we are continuing to see, and this second incident just shows that we really can’t escape it unless our legislators take action and do something to make it better,” Clausen said.

Guskiewicz discussed changes on campus since the lockdown two weeks ago

“We heard that many of the community members wanted to have more frequent updates through different means of communication, and so we acted on that already and we were able to put that into play today,” Guskiewicz said. “So that is one of the things that we’ve learned.” 

Chief James said the department is still reviewing the last lockdown and discussing additional security measures, which could also involve technology upgrades.

“Many of the things that that we may implement in the future, just simply, it just hasn’t been enough time to implement many new measures,” James said.