US Department of Defence finds that Sufiyan Barhoumi is no longer a threat to US national security after being held in prison for two decades.

In this Feb. 6, 2016, file photo, an army captain walks outside unoccupied detainee cells inside Camp 6 at the US detention center at Guantanamo Bay, Cuba.
In this Feb. 6, 2016, file photo, an army captain walks outside unoccupied detainee cells inside Camp 6 at the US detention center at Guantanamo Bay, Cuba. (AP)

The Pentagon has announced it has repatriated an Algerian man detained for nearly 20 years at the Guantanamo Bay military prison, more than five years after his release was first arranged.

Sufiyan Barhoumi had initially been suspected of having been an instructor at an Al Qaeda camp and training Saudi militants in making remotely detonated explosive devices.

But in 2008, the Pentagon dropped all charges.

In 2016, a review board determined that the "law of war detention of Mr. Barhoumi was no longer necessary to protect against a continuing significant threat to the national security of the United States," the US Department of Defense said in a statement on Saturday.

A Trump administration policy, however, had effectively halted most such transfers.

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Guantanamo prison

Thirty-seven detainees now remain in the detention center on the southern coast of Cuba, the Pentagon said.

Eighteen of them are "eligible for transfer" and seven are eligible to go before a review board, while 10 others — including the presumed mastermind of the 2001 terror attacks, Khalid Sheikh Mohammed — have been charged in the military commission system, and two others convicted.

The 2016 review found that while Barhoumi was involved in various extremist groups, he was not a member of Al Qaeda nor the Taliban.

Barhoumi was the sole Algerian among those eligible for transfer. The Pentagon said his release was subject to assurances from Algeria that he would be treated humanely and not pose a threat in the future.

The statement said the United States "appreciates the willingness of Algeria and other partners to support ongoing US efforts... focused on responsibly reducing the detainee population and ultimately closing the Guantanamo Bay facility."

The Joe Biden administration has been working to reduce the number of detainees at Guantanamo — a sprawling facility opened amid the US "war on terror" — and eventually close the facility.

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Source: AFP