Citing "security-related issues," two federal judges last week ordered all federal inmates to be moved from the Silverdale Detention Center.
Judges Sandy Mattice and Travis McDonough issued the verbal order on Feb. 13, said David Jolley, U.S. marshal for the Eastern District of Tennessee.
All 52 federal inmates were removed the following day. Forty-four men were relocated to the Hamilton County Jail, and eight women were taken to the Bradley County Jail, authorities said.
It's not clear exactly what is creating the concern, but Jolley said that no specific threats had been made against the federal detainees.
"They aren't being targeted," he said. "It's specific to the facility. [The judges] have concerns about some security issues at the facility itself and didn't want us to continue to house any of our federal detainees there."
Hamilton County Sheriff Jim Hammond said Saturday that in order to make room for the 44 male federal detainees, an equal number of non-federal inmates were moved out of the downtown jail and taken to Silverdale, which is managed by private prison operator CoreCivic.
"We have been made aware of issues at Silverdale and an investigation is currently underway by our Criminal Investigations Division," Hammond said in a statement.
Sheriff's office officials did not return a request Wednesday for clarification of the nature of the criminal investigation or whether there are concerns for the safety of the state inmates who remain housed at Silverdale.
"CoreCivic cares deeply about every person in our care, and we work hard to ensure those in our facilities are treated respectfully and humanely," CoreCivic spokeswoman Amanda Gilchrist said. "All of our contracted facilities, including Silverdale Detention Center, are monitored very closely by the government, and each and every one is required to undergo regular review and audit processes that include ensuring an appropriate standard of living for all inmates and detainees.
"We appreciate the strong oversight by our government partners and remain committed to operating safe, secure facilities."
Gilchrist did not respond to a request to confirm whether any CoreCivic employees were under internal investigation.