Ohio’s Marion Correctional Institution is now the biggest single-source hotspot of coronavirus cases in the United States, The New York Times reported on Monday. More than 70 percent of inmates have tested positive for the novel coronavirus, state officials said late Sunday. To date, more than 471 people have died and 11,602 more have been infected with the virus across the state, according to the Ohio Department of Health. Of those infected, about 21 percent are in the state’s prison system—with a majority of that number, about 1,828 inmates, at Marion. State officials said Sunday that while there have been no reported deaths among the inmates, the 667 remaining prisoners who have not yet tested positive are now in quarantine.

“Throughout our mass-testing process, we have found many individuals who are testing positive for COVID who are asymptomatic,” JoEllen Smith, a corrections department spokeswoman, told the Marion Star. “We are also working with local hospitals to onboard individuals who are interested in providing medical support to our facilities and who are available and qualified to do so.”