The justice department said on Wednesday that it worked with the governments of Albania and Spain to "ensure the transfers took place under appropriate security measures and consultations".
Barack Obama, the US president, had pledged to close the prison by last month, but 188 people continue to be imprisoned there.
He reiterated his commitment to shut down the prison last month, saying: "We will close Guantanamo prison, which has damaged our national security interests and become a tremendous recruiting tool for al-Qaeda."
But his administration has encountered various legal and political hurdles in trying to close the jail, including finding alternative places to continue holding some of the inmates.
Since his administration took office in January 2009, 48 detainees have been transferred overseas and one has been sent to New York to face criminal charges for the 1998 bombing of US embassies in Africa.
Yemeni petitions rejected
Separately, a US judge in Washington has rejected petitions by two Yemeni detainees, Suleiman Awadh bin Agil al-Nahdi and Fahmi Salem al-Assani, to be released from the Guantanamo prison.
About 32 detainees have won release from Guantanamo through petitions in US courts while 11 have had their requests rejected.
Last month, Obama suspended the transfer of Guantanamo detainees to Yemen following revelations that Umar Farouk Abdulmutallab, the Nigerian man accused of trying to destroy a Detroit-bound US airliner on December 25, reportedly received al-Qaeda training in Yemen.
The suspension also came shortly after reports that at least a dozen former Guantanamo prisoners had rejoined al-Qaeda in Yemen.
Around half of the detainees left at Guantanamo are from Yemen, and some of them had already been cleared to be sent home before the suspension.