The Defense Department is eyeing detention facilities in the continental United States for a suitable site to house detainees from Guantanamo Bay, Cuba, Secretary of Defense Ashton Carter said Thursday.

The administration is redoubling efforts to transfer eligible detainees–about 50–to nations willing to accept them and keep a watchful eye on their activity. The remainder of the 116 prisoners the U.S. government has declared threats, and thereby unfit for release will be relocated to a suitable facility in the continental United States, Carter said.

Incoming Defense Secretary Ashton Carter
Incoming Defense Secretary Ashton Carter

Carter has sent out teams to evaluate potential detention sites, to “examine the investments required to make facilities suitable for holding this second group of detainees.”

The teams have begun their research at Fort Leavenworth, Ky., and Naval Consolidated Brig in Charleston, S.C., to gather information on how the military holds prisoners and whether such facilities are adequate for holding the Guantanamo detainees in question. Carter stressed that the evaluation of specific facilities does not mean they are the short list for housing the detainees.

“We will also be assessing other locations in coming weeks,” he said. “Ultimately, the facility surveys will provide me, the rest of the president’s national security team, and Congress with some of the information needed to chart a responsible way forward and a plan so that we can close the detention facility at Guantanamo and this chapter in our history once and for all.”

There are two groups of detainees at Guantanamo that have to be addressed, Carter said: Those that are eligible for transfer to foreign nations and those that, “in the interest of national security should remain under law-of-order detention.

“Finding a solution for these individuals involves complicated negotiations with international partners, extensive consultations with leaders of national security and legal organizations and final approval by me. My responsibility to assess that any risk of transfer has been mitigated is not only the law, but common sense. We do this carefully, we do it deliberately.”

Carter already has approved the transfer of several detainees from Cuba to foreign countries and he said he will continue to do so when appropriate.

“Still, I have stressed that transferring this group of detainees represents only one complex piece of this equation,” Carter said. “We cannot, in fact, close Guantanamo until we find a solution for the second portion of the Gitmo detainee population, namely those who are not eligible for transfer.”

Carter called for a “security-focused plan” to relocate the detainees that are to remain jailed to the continental United States. The Defense Department is searching for an alternative defense detention facility to house those prisoners, Carter said.

“I’m pleased that many members from both sides of the aisle in Congress have indicated their interest and willingness to consider such a plan,” Carter said.