LANSING — Four Michigan prisoners have now tested positive for the coronavirus, plus three Michigan Department of Corrections employees and one parolee, an agency spokesman said Wednesday.

Dozens more prisoners are in quarantine after potential exposure to a prisoner who tested positive, Chris Gautz said.

Two prisoners at Parnall Correctional Facility tested positive on Tuesday, Gautz said. A prisoner at Newberry Correctional Facility also tested positive Tuesday, Gautz said.

Earlier, a prisoner at Kinross Correctional Facility in the Upper Peninsula tested positive, but the testing was done at a hospital in the Lower Peninsula, Gautz said.

More:First Michigan prisoner tests positive for coronavirus

More:Coronavirus is changing life for Michigan prisoners, too. Here's how.

The spread of the coronavirus inside prison walls is a major concern for prison staff, prisoner advocacy groups, prisoners and their families.

The parolee is someone who was tested at the Detroit Reentry Center on March 23, was paroled on March 24 and had his test results returned as positive later that day, Gautz said.

"The Wayne County Health Department was notified upon his release and the parolee was advised to self-quarantine. Staff and other prisoners who may have had close personal contact at the facility are being notified," he said.

Three Corrections Department employees have tested positive: A Jackson County probation officer, an employee of the Detroit Detention Center, and an employee of Thumb Correctional Facility in Lapeer, Gautz said.

"When we have a prisoner who the county health department agrees needs to be tested, we then identify any prisoners (and staff) who may have been in close personal contact with that prisoner," he said. "Those prisoners are quarantined until the prisoner’s test comes back. If it’s negative, they are released from quarantine, as is the one who was tested."

Contact Paul Egan at 517-372-8660 or pegan@freepress.com. Follow him on Twitter @paulegan4. Read more on Michigan politics and sign up for our elections newsletter.