GUANTANAMO BAY NAVAL BASE, Cuba -- The review board considering whether to release some U.S. prisoners at the prison at Guantanamo has approved the release of a Yemeni captive of 14 1/2 years, meaning that 21 detainees could leave the prison with security arrangements before President Barack Obama leaves office.

Another 10 of the last 59 prisoners are charged at the war court, called military commissions, and now 28 are classified as indefinite detainees in the war on terrorism: "forever prisoners."

Now, 21 of Guantanamo's last captives are cleared for release -- and 28 are forever prisoners.

Salman Rabeii "traveled to Afghanistan in August 2001 where he received training from al-Qaida and possibly fought in Tora Bora before his capture," according to a July 28 intelligence profile. The Periodic Review Board rejected his release in May, declaring him too dangerous to go from Guantanamo.

But a Dec. 1 decision, released over the weekend, declared him cleared him for transfer. It recommended that he be sent to a Persian Gulf nation. Rabeii was candid at his most recent hearing, on Nov. 1, the board said, and essentially agreed with aspects of his profile compiled by U.S. military intelligence.

So in this instance, the board isn't rejecting an earlier assessment. Instead, it found that Rabeii "does not currently demonstrate an extremist mindset or appear to be driven to re-engage by extremist ideology."

Rabeii's latest attorney, Shelby Sullivan-Bennis of the London-based legal defense firm Reprieve, told the board that the Yemeni has a sister living in London. Wherever he ends up, she said, he would be able to benefit from Reprieve's Life after Guantanamo program, which helps captives return to free society.

She called him a self-taught English speaker with an "impressive network of family to provide both emotional and financial support."

The inter-agency board issued the decision while there is still time for Secretary of Defense Ashton Carter to arrange transfers before Obama leaves office. By law, Carter must give Congress 30 days notice of a transfer, meaning the Obama administration could transfer only cleared captives for whom notice has been provided by Dec. 21.

It is not known what President-elect Donald Trump will do with transfer plans once he takes charge. But he has expressed dissatisfaction with the prisoner releases.