A University of North Carolina doctoral student has been charged in the fatal shooting of a professor on the school’s Chapel Hill campus on Tuesday, Reuters reported.

Court documents show that Tailei Qi, 34, was quickly arrested by law enforcement and charged with first-degree murder and carrying a weapon on a college campus in the 2019 shooting death of Jijie Yan, an associate professor of applied physics at the school.

During the armed attack, some students barricaded themselves, while others jumped from the building to escape the attacker.

The university’s website revealed that Qi was a doctoral student who joined Yang’s research group in January 2022.

It is currently unknown what prompted the gunman to attack the campus lab on Monday afternoon.

Reports of the shooting brought the institution, which has about 32,000 students, as well as about 4,100 teachers and 9,000 technical staff, to a standstill.

Nearby public schools were also closed on the first day of classes after summer vacation.

The university said Tuesday it has set up a hotline for students and faculty who need to talk about the incident, as well as those who need other counseling services.