Dozens more are expected to follow when officials can find them homes.
But a looming dilemma is what to do with the 30 Yemenis whose release had been cleared but later put on hold in the wake of the attempted Christmas Day bombing of Northwest Flight 253 by Nigerian Umar Abdulmutallab, who is believed to have received al-Qaeda training in Yemen.
The administration halted the repatriation of all Yemenis from Guantanamo amid concerns about the country's security and record of breeding terrorism. Tom Malinowski of Human Rights Watch says this is a potential problem.
"If Gitmo stays open as a camp that is mostly for Yemenis, I can't imagine a better gift to al-Qaeda in the Arabian Peninsula," he said.
Lawmakers have also expressed concern with the number of former Guantanamo detainees returning to the battlefield. While the exact number is unclear, the Pentagon estimated in January a 20 percent recidivism rate, up from 14 percent six months before.
Republicans alarmed by the rising number say it's one reason Guantanamo should be left open. But the Obama administration has countered that all of the former detainees who have returned to terrorist activities were released or transferred under the Bush administration.
Furthermore, the administration says it has instituted a comprehensive review process involving multiple agencies to monitor detainees. Still, the prospect of released detainees returning to the battlefield at all instills more than a little uneasiness among policymakers who are weighing just that.
Another sticking point revolves around 48 prisoners the administration says it will hold indefinitely under the laws of war. U.S. law forbids the transfer of such uncharged individuals to U.S. soil but the administration wants Congress to change the law.
Human rights groups are opposed to the idea of bringing the uncharged detainees to Thomson Prison or any other facility inside the United States for fear that it will start a new legal precedent.
"It's bad enough that indefinite detention without charge is going on in places like Guantanamo and Afghanistan, but to bring it to U.S. shores creates a whole other level of problems," Chris Anders of the American Civil Liberties Union said. "Right now in the United States, there are zero people being held indefinitely without charge. If the 48 are brought to Thomson it will make it easier for the U.S. to add to that number."
Malinowski of Human Rights Watch agreed, saying he's concerned the administration might "institutionalize the problem" of the uncharged 48 by "making detention without charge a permanent feature of the fight against terrorism."
Furthermore, these groups say, under the Geneva Convention rules for treatment of prisoners during war, the detainees who remained uncharged are supposed to be free from detention in an environment consistent with a near lockdown of a supermax penitentiary.