The authorities accused a group of students of trying to hold an "illegal gathering" before invading lecture theatres on the campus.
"They assaulted lecturers and students and destroyed public properties, thereby creating an atmosphere that was not conducive to learning," a statement said.
The students have been protesting against a new academic system. Disturbances intensified on Thursday when witnesses said hundreds of were targeted by police firing teargas.
Around 40,000 students are based in at the university in the capital of the west African state.