A graduate student at the University of North Carolina at Chapel Hill has been charged in the fatal shooting of one of his professors on Monday, a killing that spread fear across the campus and forced an hourslong lockdown, according to court documents.

The student, Tailei Qi, 34, was charged with first-degree murder and possession of a firearm on educational property in the killing of Zijie Yan, an associate professor in the applied physical sciences department, inside a campus lab, according to court documents filed in Orange County Court in Hillsborough, N.C.

Mr. Qi made a brief appearance in court on Tuesday afternoon and was ordered held without bond until his next court appearance on Sept. 18. He did not enter a plea. The public defender who represented him did not immediately respond to an email and phone call seeking comment.

Although first-degree murder is a capital crime in North Carolina, Jeffrey L. Nieman, the Orange County district attorney, said he would not seek a death sentence. The charge carries a minimum sentence of life without parole, Mr. Nieman said.

Brian James, chief of police at U.N.C.’s Chapel Hill campus, said at a news conference on Tuesday that Mr. Qi and Professor Yan “knew each other and the suspect went directly to the victim and then left Caudill Labs.” After the professor was shot, the campus went into lockdown and officers swarmed the area. Chief James said it was too early to determine a motive.

Mr. Qi was arrested about 90 minutes after the shooting, although the gun that was used has not been recovered, and it’s not clear whether it was bought legally or illegally, Chief James said.

Mr. Qi, a doctoral student in applied physical sciences, was one of three graduate students in Professor Yan’s research group and was a co-author of at least two research papers with him, according to the group’s website. Mr. Qi joined the group in January 2022, the website said.

Professor Yan earned a Ph.D. in materials engineering from Rensselaer Polytechnic Institute and joined the U.N.C. faculty in the applied physical sciences department in 2019, according to a university website.

He was originally from the Hubei Province in central China, and obtained bachelor’s and master’s degrees from Huazhong University of Science and Technology in Wuhan, China, the news site nny360.com reported in 2015. His research interests included optical trapping and manipulation, holography, microfluidics and nanomaterials.

Kevin M. Guskiewicz, chancellor of the University of North Carolina at Chapel Hill, said on Tuesday that the university planned to ring the campus bell tower and observe a moment of silence at 1:02 p.m. on Wednesday in honor of Professor Yan.

“He was a beloved colleague, mentor and friend to many on our campus,” Dr. Guskiewicz said in a message to the campus community. “Please join me in thinking and praying for his family and loved ones during this difficult time.”

Mr. Qi grew up in a small village in Henan Province in central China, according to a 2010 local media report profiling him and his younger brother for achieving identical high scores on the country’s national college entrance examination.

The story highlighted how his family relied on farming six acres as their only source of income and how the two brothers helped their parents with heavy labor.

The report also stated that the family was worried about paying college tuition for the two sons because Mr. Qi’s father suffered from liver disease and his mother had leg problems.

The shooting shattered the sense of calm on campus just days after summer vacation had ended and classes had resumed at the university, which has more than 30,000 undergraduate, graduate and professional students.

Chief James said the police received a 911 call reporting that shots had been fired at Caudill Labs at 1 p.m.

Soon after, the university sent an alert advising people in the area to go inside and to stay away from windows. The university warned of an “armed, dangerous person on or near campus.”

Nearly an hour and a half later, the university said in another alert that the shelter-in-place order remained in effect and that there was a “suspect at large.”

Jake Diana, a Ph.D. student and teaching assistant, said that he was just about to hold his first class for the semester when, just after 1 p.m., he saw a police car zoom down South Road, near the site of the shooting, and heard campus sirens blaring.

“I was terrified,” he said, adding that he rushed to a nearby conference room with more than a dozen students, where they barricaded the door with a bookcase, switched off the lights, silenced their phones and lay on the ground.

Mr. Diana, 28, said he then texted his friends and family and began praying. “I said to God, I said, ‘I have to get through this.’ I said, ‘I want to do so much with my life.’”

Mr. Qi was arrested on Monday at about 2:30 p.m., Chief James said. At 4:14 p.m., the university ended the lockdown and declared that the situation was “all clear.”

Dr. Guskiewicz said on Monday that it had been “a truly tragic day for our campus community.”

“This loss is devastating, and the shooting damages the trust and safety that we so often take for granted in our campus community,” he said. “We will work to rebuild that sense of trust and safety within our community.”

Livia Albeck-Ripka, Emily Cataneo and Amanda Holpuch contributed reporting.