Pentagon officials said those released included 23 Afghans and three Pakistanis.
"They no longer were deemed a threat and they no longer had intelligence value," said Major Michael Shavers, a Pentagon spokesman.
The Pentagon would provide no other information on the detainees or the transfer, citing operational and security reasons.
But they were the latest in a series of detainees who have been either released or turned over to authorities of their home countries for further detention.
The releases came less than a week after five Britons were turned over to British authorities, flown to London and quickly released without charges.
The Britons have charged in newspaper interviews and through lawyers that they were beaten and mistreated during their two years in US military custody.
The Pentagon on Monday dismissed those allegations as "lies" and said they would not be investigated because they lacked credibility.
"These allegations are fabrications. These are lies," said Shavers.
"These allegations (of mistreatment at Guantanamo) are fabrications. These are lies. All the detainees were treated humanely and to the extent appropriate and consistent with military necessity in accordance with the third Geneva Convention of 1949"
Major Michael Shavers,
"All the detainees were treated humanely and to the extent appropriate and consistent with military necessity in accordance with the third Geneva Convention of 1949.
"Because these are lies and fabrications, they are not credible. If they were credible allegations of illegal conduct, then we would investigate."
Asked how the Pentagon could determine whether the allegations were lies without an investigation, the spokesman said: "We do not do what they are alleging."
By the Pentagon's tally, 119 detainees have been released from Guantanamo Bay so far.
Twelve others - four from Saudi Arabia, one from Spain and seven from Russia - were repatriated for continued detention in their home countries.
More than 600 prisoners are being held as "enemy combatants" at Camp Delta, a maximum security prison at a US naval base at Guantanamo.
President George Bush has designated six detainees as eligible for trial by military commissions, but so far charges have been brought against only two prisoners.
Bush has called the Guantanamo
Human rights groups and some governments have criticised the indefinite detentions, saying the prisoners are in a legal limbo with charges or access to lawyers.
The Pentagon, which defends the detentions as in keeping with the laws of armed conflict, unveiled plans earlier this month to establish military boards that will review the status of prisoners on an annual basis.