The Pentagon says four detainees held at the Guantanamo Bay U.S. military detention facility have been repatriated to Afghanistan.
A Pentagon statement said on December 20 said the men -- Shawali Khan, Khi Ali Gul, Abdul Ghani, and Muhammad Saeed -- had been moved from the prison after a comprehensive review of their case.
An unnamed U.S. official said the four detainees were flown to Kabul overnight aboard a U.S. military plane and released to Afghan authorities.
The U.S. Embassy in Kabul on December 20 issued a statement saying it had "full confidence in the Afghan government's ability to mitigate any threats these individuals may pose and to ensure that they are given humane treatment."
The statement said the transfer "demonstrates Afghan sovereignty and U.S. trust in the strength of Afghan government institutions."
U.S. officials are citing the transfer as a sign of their confidence in new Afghan President Ashraf Ghani.
Obama administration officials said they worked quickly to fulfil the request from Ghani, in office just three months, to return the four -- long cleared for release -- as a gesture of reconciliation and a mark of improved U.S.-Afghan relations.
There is no requirement that the Afghan government further detain the men. Afghanistan's High Peace Council, a government-appointed group, has confirmed the transfer, without identifying the men.
The council said the four "will be reunited soon with their families."
There are now 132 detainees at Guantanamo, the lowest number since the detention center on Cuba opened nearly 13 years ago in the wake of the September 11, 2001, terror attacks.
Of that number, 64 have been approved for transfer.
U.S. President Barack Obama pledged to shut the prison, which is located on Cuban territory, when he took office nearly six years ago, citing the damage it inflicted on the United States' image around the world.
But Obama has been unable to do so, partly because of obstacles posed by the U.S. Congress.
Also on December 20, Romania announced it would send an extra 450 troops to Afghanistan starting next year in addition to the previously announced 200 military instructors and trainers.
Outgoing President Traian Basescu said Romania's Supreme Defense Council has approved the deployment of additional soldiers, who will be tasked with guarding the Kandahar airport and military base in southern Afghanistan.
Romania had initially committed some 200 troops to participate in the Resolute Support mission which will train Afghan forces beyond 2014.
Basescu, speaking in Bucharest at his final news conference before leaving office on December 21, said the decision was made after a request from Romania's allies.
At its peak in 2010, Romania's contingent in Afghanistan numbered 1,600 troops. Romania lost 76 soldiers in Afghanistan, including 20 killed in action.
The 13-year NATO-led International Security Assistance Force (ISAF) mission ends this month, but some 12,500 foreign soldiers -- mostly from the United States -- will remain in the country in 2015 in a supporting role.
Obama, in his weekly address on December 20, hailed the end of the Afghan mission, saying, "our war there will come to a responsible end."