A student fatally stabbed University of Southern California psychology professor Friday, police said. The professor, identified as Bosco Tjan in a letter released by the university, was pronounced dead at the scene by the Los Angeles Police Department.

Tjan, also the co-director of the Dornsife Cognitive Neuroimaging, joined the USC faculty in 2001 and was an expert in perception, vision, and vision, cognition, Nikias wrote.

According to the Associated Press, public records indicate Tjan was a 50-year-old married father of one.

According to the LAPD, Tjan was killed inside the Seeley G. Mudd building around 4:30 p.m. The suspect has been taken into custody and transported to a local police station. Police say they believe the suspect targeted Tjan and used a knife to attack him.

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