CHAPEL HILL, N.C. (AP) — There have been more than 450 reports of students at the University of North Carolina at Chapel Hill violating COVID-19 safety rules set by the school, according to a report released by the university.

The report released Monday said there were about 55 cases of students being removed from campus housing for breaking the university’s rules. The majority of the cases resulted in written warnings and other lesser disciplinary actions. In 60 of the cases, a student was not identified or found responsible.

When students began classes at the campus this fall, they had all signed agreements to follow the school’s virus safety guidelines that includes wearing masks and social distancing, The News & Observer reported.

The report does not provide details on the incidents, but said the complaints were made between Aug. 1 and Oct. 31.

The school closed dorms and moved classes online after spikes in coronavirus cases were reported in residence halls in August. But most students who moved off campus and stayed in the area, said Amy Johnson, the school’s vice chancellor for student affairs.

Students are scheduled to move back into their dorms in January for the spring semester.