Gov. Andy Beshear said almost 400 people have tested positive for COVID-19 at Green River Correctional Complex, a state prison in Central City.

Beshear said the state tested more than 1,000 people there, including inmates, staff and others that have come into the facility, and about 40 percent of the results came back positive for the virus.

“This is a concerning situation at that facility,” Beshear said.

Kentucky saw a large jump in coronavirus cases on Tuesday, with 625 new cases–the highest daily increase. Beshear attributed the spike to extensive testing at Green River and a lag in reporting from over the weekend.

He said the state is trying to expand testing efforts at state prisons, long-term care facilities and other potential hot spots for the virus.

Despite the high numbers of new cases, Beshear said he still believes the pandemic is “plateaued” in Kentucky and the state can move forward with gradually reopening.

“In the general population, we believe right now it’s at a level where if we take all these precautions we can do this safely. But we’re watching the numbers every day.” Beshear said.

Of Tuesday’s new cases, 309 were from Green River. There are two prison employees and two inmates currently in the hospital, with one staff and one inmate in the ICU.

Executive Cabinet Secretary J. Michael Brown said the state is still waiting for about 50 test results from the facility, but they almost have a complete snapshot of who has the virus.

“Then we can really follow out this plan to try to contain it where it is,” Brown said.

The state plans to divide the prison population into different housing units based on whether they’ve tested positive or negative for coronavirus, and whether they’ve been in contact with anyone who tested positive. Medically-vulnerable people will also be kept apart from the general population.

Shortly after Beshear’s press conference, the ACLU of Kentucky called the outbreak at Green River “shocking, but not surprising,” criticizing officials for not taking steps to isolate people who tested positive at the facility weeks ago.

In a statement, ACLU of Kentucky legal fellow Aaron Tucek said officials should aggressively sanitize facilities and drastically reduce incarcerated populations.

“Detention should not be a death sentence,” Tucek wrote.

Beshear reported 14 new deaths associated with coronavirus on Tuesday, including the youngest so far—a 35 year-old from Jefferson County.

There have been 275 deaths in Kentucky so far during the pandemic.

Ryland Barton is the Capitol bureau chief for Kentucky Public Radio.