The Obama administration is secretly preparing to transfer up to 24 prisoners out of the U.S. military detention center Guantánamo Bay in Cuba by the end of the summer, the Guardian and Fox News report, citing unnamed sources.

As the first news outlet to shed light on the plans, The Guardian notes that the transfer to multiple countries is expected to occur by the end of July.

Currently, there are 80 prisoners detained at the Guantánamo facility, down from the 242 when President Barack Obama took office.

The majority of the remaining detainees are from war-ravaged Yemen, where al-Qaeda in the Arabian Peninsula (AQAP) is reportedly flourishing.

An unnamed official told Fox News that the prisoners still being held at the detention center, commonly known as Gitmo, have been deemed the “worst of the worst.”

“The official was not confident the countries ultimately receiving these terrorists would be up to the task of keeping them locked up or even tracking them,” reports the network. “While an Obama administration task force found many detainees should remain in U.S. custody, a new review board in 2011 looked at the cases and reached a different conclusion, though much of the evidence was the same.”

The review process has approved an estimated 28 detainees for transfer, notes The Guardian, adding, “so the men’s departure would nearly empty Guantánamo of such designated detainees, substantially clearing a backlog that has lasted years.”

At the end of March, the Miami Herald reported that 40 captives were expected to get their first hearing in front of the review board by the end of this year.

If President Barack Obama moves ahead with the reported plans, up to 56 prisoners would remain at Gitmo.

They are considered “too dangerous to release,” acknowledges The Guardian.

Not all of the 24 prisoners expected to be released have received certification by Secretary of Defense Ash Carter as required by law, adds the U.K.-based news outlet.

Carter’s approval is required ahead of notification to U.S. lawmakers.

In January, Lee Wolosky, the U.S. State Department’s envoy for shutting down the U.S. military prison, vowed to empty Guantánamo of detainees eligible for transfer “by this summer.”

President Obama has pledged to close the Gitmo prison but has met stiff resistance from a bipartisan group of lawmakers.

Nevertheless, the Pentagon has submitted a proposal to Congress to close down the facility, which includes a provision to transfer prisoners to facilities on U.S. soil.

Current law prevents the Obama administration from transferring Guantánamo detainees to the U.S.

Paul Lewis, the Pentagon’s special envoy for Guantánamo detention closure, conceded in March that detainees liberated from the prison have killed Americans.

That same month, the office of the Director of National Intelligence (ODNI) reported that as of mid-January, about 3 out of every 10 detainees were suspected or confirmed to have engaged in terrorist activities.

Thomas Joscelyn, senior fellow at the Foundation for Defense of Democracies and senior editor of The Long War Journal told House lawmakers Tuesday that the effort to close down the prison is “all about ideologically driven policy. It’s not about the actual assessment of the risks of these individuals.”