According to Inspectors General of Police S. Kailun and Clay Khongsai, the police entered the campus right after midnight on the basis of a complaint by Vice Chancellor in-charge K. Yugindro saying that on Thursday he was prevented from taking charge.
The police action triggered massive protests by the students leading to scuffles that prompted the police to fire several rounds of tear gas shells to disperse the crowd.
Amar Yunan, a professor, said some students sustained injuries and were bleeding.
Manipur University has been gripped by unrest for the last three months or so as students and teachers demanded the removal of Vice Chancellor A.P. Pandey.
The university was shut for 85 days. Normalcy returned earlier in September when a fact-finding committee was set up to look into the charges against Pandey, who has been accused of being involved in financial and administrative irregularities.
Pandey, who has denied the charges, was suspended on September 17.
Vice Chancellor in-charge Yugindro took charge on Friday after he was forced to resign on Thursday by some teachers and students.
Internet services have been suspended in Manipur for the next five days.