Packed into a crowded federal prison complex with not enough masks, soap or hand sanitizer, and the sole doctor out sick, corrections workers in Tallahassee, Fla., were worried.

Then on Monday, a new inmate arrived and was immediately put into quarantine. And on Tuesday, a bus with almost a dozen inmates from a U.S. Immigration and Customs Enforcement detention center showed up.

They were scheduled for quarantine, too. And all had elevated temperatures.

“I just delivered hand sanitizer to the unit that the inmates will be housed in,” said Kristan Morgan, a nurse practitioner at the prison who checked the new arrivals’ temperatures. “Staff are starting to get fearful.”

In jails and prisons across the country, concerns are rising of a coronavirus outbreak behind bars. Already, cases have been reported. On Friday, someone who works in a Washington State prison tested positive for the virus, and the day before, the sheriff in Hancock County, Ind., said a staff member at the local jail was being isolated at home after a positive test. On Tuesday night, New York State confirmed that an employee at the Sing Sing Correctional Facility had tested positive.