Scores of students of the Banaras Hindu University staged an overnight protest outside the campus gate after a professor accused of sexually harassing women students was reinstated and allowed to take classes.
The students have been protesting since Saturday evening, demanding that the professor be punished.
Professor S K Chaubey of the Zoology department was suspended in October last year on the charges of sexual misconduct levelled by some students of his department.
In June, the BHU executive council, the highest decision-making body of the varsity, revoked the suspension of Chaubey, however, it censured and restricted him for taking academic classes.
Chaubey returned to taking classes a few days ago, triggering protests, a student said.