COLUMBUS, Ohio (AP) — Ohio inmates make up nearly one in four of the state’s coronavirus cases following a spike in identified infections as universal testing takes place inside three state prisons.

Figures released Sunday show 1,828 positive tests at Marion Correctional Facility in north-central Ohio, out of about 2,500 total inmates, according to the Department of Rehabilitation and Correction.

In addition, 109 employees at Marion have tested positive, out of a total of about 350 workers, which includes about 295 guards. One Marion prison guard died earlier this month.

Systemwide, 2,400 inmates have tested positive and six have died, including five at Pickaway Correctional Facility in central Ohio, where 384 inmates have tested positive out of a population of about 2,000. Even the head of the prison guards’ union, Christopher Mabe, is in self-quarantine after his wife, a guard at Lorain Correctional Institution, tested positive.

The spike in prison infections sent the state’s tally of cases on Sunday to more than 11,600, which includes 471 deaths.

Inmate rights groups have called on Republican Gov. Mike DeWine to release thousands of the state’s 49,000 inmates to prevent the spread of the virus — among them Policy Matters Ohio, the American Civil Liberties Union, the Ohio Organizing Collaborative and the Juvenile Justice Coalition.

To date, DeWine has released just seven inmates, and requested a review of 198 others, most of them elderly, with sentences running out soon; pregnant inmates; and women with children living with them behind bars.

Members of the Ohio National Guard are helping staff the Pickaway and Marion facilities, and are also assisting at the federal prison in Elkton in eastern Ohio, where six inmates have died.

On April 10, DeWine announced that facility-wide testing would be done at Marion, Pickaway and the Franklin Medical Center in Columbus. At that time, 36 inmates and 58 employees had tested positive, most at Marion and Pickaway.

That decision came two weeks after a Marion employee first tested positive on March 29. Although the prison system assessed every Marion staff member afterward, it was up to inmates to tell medical staff if they were ill, according to an email the prisons director sent to DeWine’s office on March 30.

“Nothing of concern has surfaced,” prisons director Annette Chambers-Smith said of the inmate situation in the March 30 email, a copy of which was obtained by The Associated Press through a records’ request.

For most people, the virus causes mild or moderate symptoms that clear up in a couple of weeks. Older adults and people with existing health problems are at higher risk of more severe illness, including pneumonia, or death.

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