The two men from Tunisia and three from Yemen had been cleared for release from the prison by a government task force but could not be sent to their homelands. The U.S. has sent hundreds of prisoners from Guantanamo to third countries but this is the first time Kazakhstan has accepted any for resettlement.

Their release brings the prison population at Guantanamo to 127, according to a Pentagon statement.

The U.S. identified the Tunisians as 49-year-old Adel Al-Hakeemy, and Abdallah Bin Ali al Lufti, who military records show is about 48.

The Yemenis are Asim Thabit Abdullah Al-Khalaqi, who is about 46; Muhammad Ali Husayn Khanayna, who is about 36; and Sabri Mohammad al Qurashi, about 44.

All five had been captured in Pakistan and turned over to the U.S. for detention as suspected Islamic militants with ties to al-Qaeda. None of the men were ever charged and a government task force determined it was no longer necessary to hold them.

The U.S. does not say why they could not be sent home but the government has been unwilling to send Yemenis to their country because of unrest and militant activity there while in the past some Tunisians have feared persecution.

Nearly 30 prisoners have been resettled in third countries this year as part of President Barack Obama's renewed push to close the detention center over opposition from Congress.