CHARLOTTE (AP) — Students at the University of North Carolina at Charlotte were told to stay inside their dorm on Friday after the virus that causes COVID-19 was detected in the dorm’s wastewater, officials said.

Emergency management officials tweeted the news Friday morning, saying that the virus was detected during routine sampling, news outlets report. Officials didn’t name the residence hall where the virus was detected, citing the privacy of the residents.

Under university’s protocol, residents in the hall must remain in the building until they are tested for coronavirus. The tests were expected to take place Friday afternoon.

No one living in the dorm has reported COVID-19 symptoms, “and no additional residence halls are affected at this time,” the school said.

The school said anyone testing positive or identified as a close contact of anyone who tests positive will be placed in quarantine/isolation in accordance with the school protocols.

UNC Charlotte reached record enrollment of more than 30,000 students for the fall semester and resumed in-class learning on Thursday for some studies.

The school has nine active COVID-19 cases, according to its COVID-19 Dashboard. Five are on-campus students, four of whom have been isolated and one quarantined, according to the Dashboard.