Toronto police are investigating a stabbing at the University of Toronto (U of T) Sept. 10.

A 21-year-old female U of T student entered a professor’s office and attacked him, according to Toronto police.

“She displayed a knife and began slashing at him,” David Hopkinson, media relations officer for Toronto police, said.

“He was able to hold her down,” Hopkinson said. “There were other people who heard the commotion [and] came to his assistance.”

Professor Sean Uppal suffered minor injuries and was taken to hospital.

Xiao Yue Zhou, the student, has been charged with aggravated assault, assault with a weapon, criminal harassment, and possession of a weapon.

Hopkinson was unable to say if there is any connection between Uppal and Zhou.

Uppal was a popular professor at U of T, and many students said they have no idea what could have provoked her.

“He is one of the best professors I’ve ever had,” said Yana Staroverova, a former student of Uppal. “I’d call him ‘Dr. House of math.’”

“Every time I went to his office hours, there were always different groups of people asking for help,” said Jonathan Liang, another former student of Uppal.

Zhou is to appear in court again Oct. 8.