SEATTLE (AP) — At least 80 students living in a dozen fraternity houses near the University of Washington campus have reported testing positive for COVID-19, with hundreds of results pending.

The university learned Saturday that three 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.

By Tuesday, the university said at least 38 students tested positive. Ma says 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.