More than 100 students living in fraternity houses near the University of Washington campus have reported testing positive for COVID-19, with hundreds of results pending. The Interfraternity Council, a student-led governing board for UW fraternities, said that at least 105 residents living in 15 fraternity houses have self-reported that they tested positive, CBS affiliate KIRO-TV reports.

The university learned Saturday that some fraternity residents had symptoms of COVID-19, and public health officials noticed a spike in cases among people ages 18 to 20, according to university spokeswoman Michelle Ma.

Ma said more than 800 students have been tested since Monday in response to the Greek system outbreak. The university expects to have an updated case count early next week. The Interfraternity Council has asked fraternity houses to stop holding social events, Ma said.