A professor at George Mason University was lecturing a class Wednesday afternoon when an intruder burst into the room, jumped onto a desk and pepper-sprayed him in the face, saying he was making a citizen’s arrest.

Tyler Cowen is described as one of the most well-known professors at the university. (Image source: Wikimedia)

Tyler Cowen is described as one of the most well-known professors at the university. (Image source: Wikimedia)

Though the university has not released the name of the professor who was attacked, WJLA-TV identified the victim as Tyler Cowen. Cowen was teaching at George Mason’s campus in Arlington, Va., and was apparently talking about vigilantes at the time, ironically, causing some of the students to initially think the incident was a setup, according the news station.

The suspect fled after spraying Cowen, but an off-duty police officer who was taking the class chased him down the hall and held him until authorities could arrive.

It is unclear what motivated the suspect, who has not yet been identified publicly. The school told the news station that the suspect was not a student. Arlington County Police spokesman Dustin Sternbeck told ARlnow that the professor didn’t know the man. Charges are pending.

“It’s definitely very concerning that someone can just come into a building and assault a professor like this,” student Shannon Orcutt told WJLA.

Watch WJLA’s report that shows the suspect being arrested:

Cowen and up to 15 students in the class at the time of the pepper-spraying were seen by medics.

George Mason University spokesman Mike Sandler told TheBlaze the campus “is safe place for our students, faculty and staff,” noting that it has its own police force.

“While we always have police officers on campus to ensure safety of our students, we have increased presence today mostly as a precaution to make people feel safer,” Sandler added.

The Arlington Police Department did not immediately responded to TheBlaze’s request for comment.

(H/T: Reason)