Duke University students were ordered to quarantine this weekend following an increase in COVID-19 cases that were “almost all linked to unsanctioned fraternity recruitment events that took place off campus,” according to a statement on the school’s website. 

Before Saturday evening’s university order, the insttitution revealed that over 180 students went into isolation after testing positive within the past week, as 200 others were possibly exposed. All undergraduate students are now required to stay in place at least until March 21, with “flagrant or repeat violators” of quarantine facing suspension. 

“This is by far the largest one-week number of positive tests and quarantines since the start of the pandemic,” the university said in the Saturday statement. 

Duke spokesman Michael Schoenfeld wrote later on Sunday that the pandemic is “still a very real danger” at the school of over 6,000 undergrads and more than 8,000 graduate and professional students.

“Those who are found responsible for organizing and hosting these events will be held accountable through the student conduct process,” Schoenfeld wrote. “This coming week will be a difficult (and we hope brief) chapter in a uniquely exhausting year and we are deeply concerned about the mental health and wellness of our students. As we get through this stay-in-place period together, we are encouraging all students to utilize the many Duke resources available, from peer-to-peer calls to virtual meals to guided meditations.”

On Twitter Monday, the school shared an update alongside a photo of flowers on campus, writing that it’s “grateful for the patience and partnership of all the members of our community who consistently prioritize the health of Durham and Duke communities.”