(The Hill) – Cornell University is shutting down its campus amid a “rapid spread” of coronavirus cases among students.

According to Cornell’s online COVID-19 dashboard, 469 students tested positive for the virus as of Tuesday, and the university had an overall positivity rate of 3.01 percent of the week of Dec.6. 

In a letter to the student body, university president Martha Pollack said due to the closures, all end of the semester final exams will be moved online and all campus activities and athletics are canceled. The school libraries are closed as well.

Pollack also said the school’s COVID-19 lab team detected evidence of the omicron variant “in a significant number of Monday’s positive student samples.”

This led to the school moving to an “alert level red” and announcing the immediate closure of the campus, the letter said.

“While I want to provide reassurance that, to date, we have not seen severe illness in any of our infected students, we do have a role to play in reducing the spread of the disease in the broader community,” Pollack wrote in her letter. “The fact that we have not experienced severe illness among our student population may lead some to ask why we are imposing such serious steps.”

This comes as more than a dozen U.S. states have reported omicron variant cases earlier this month. 

According to its academic calendar, Cornell’s last day of class was Dec. 7. Final exams are scheduled through December 11-18.