A USC student allegedly stabbed his psychology professor to death on campus Friday afternoon over what investigators are saying “was the result of a personal dispute.”

The student, 25, was arrested at the scene of the crime. According to the Los Angeles Times, he was apprehended at the scene of the crime and taken into custody without resistance. His name has not yet been released.

USC President C.L. Max Nikias reportedly identified the victim as psychology Professor Bosco S. Tjan, 50, a married father with one son. Tjan was the co-director of the Dornsife Cognitive Neuroimaging Center and, according to the school, was an expert in perception, vision and vision cognition. He had been affiliated with the private school since 2001.

“We want to make clear this was not a random act,” LAPD Det. Meghan Aguilar said, according to the Los Angeles Times. “This victim was targeted by the suspect.” 

USC President C.L. Max Nikias wrote a letter to the university community following Tjan’s death. “As the Trojan Family mourns Professor Tjan’s untimely passing, we will keep his family in our thoughts,” Nikias wrote.

According to the letter, the stabbing occured in the Seeley G. Mudd Building on campus.

Tjan’s murder came as a particular shock to those who knew him. Chris Purington, a project manager at Tjan’s lab, told KCRA3 he had never heard of anyone having a problem with Tjan and that he had no idea who would have wanted him dead.

“He was somebody who really cared about people. I know he cared about me,” Purington reportedly said through tears. “He just had this energy about him. Kinetic might be the word,” Purington told KCRA3. “He had a huge impact on my life.”

Earlier this year, 39-year-old UCLA Professor William S. Klug was killed by one of his students in a murder-suicide. Klug, a popular engineering professor, was shot and killed by Mainak Sarkar, 38, a former doctoral student who accused him of stealing his research and giving it to someone else. Klug left behind a wife and two children.

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