The United States has released a Saudi Arabian engineer who was imprisoned for more than 20 years at Guantanamo Bay military prison despite never being charged with suspected crimes following the September 11, 2001 attacks on the US.

The US Department of Defense said on Wednesday that Ghassan Al Sharbi, 48, was returned to Saudi Arabia after a review board determined in February 2022 that his detention “was no longer necessary to protect against a continuing significant threat to the national security of the United States”.

Al Sharbi was transferred to Saudi Arabia “subject to the implementation of a comprehensive set of security measures including monitoring, travel restrictions and continued information sharing,” the defence department said in a statement.

The Pentagon’s Periodic Review Board ruled in 2022 that Al Sharbi had no leadership or facilitator position in al-Qaeda and was compliant in detention. It also said he had unspecified “physical and mental health issues”.

The US said Al Sharbi had fled to Pakistan after the September 11 attacks and had received training in bomb-making. He was arrested there the next year, allegedly tortured in custody and sent to the Guantanamo prison camp.

The US military had weighed charges against Al Sharbi and several others but dropped them in 2008. Though never charged with a crime, he was also not approved for release and the US continued to hold Al Sharbi as an enemy fighter.

Al Sharbi was initially targeted because he had studied at an aeronautical university in Arizona and had attended flight school with two of the al-Qaeda hijackers involved in the 2001 attacks.

He becomes at least the fourth Guantanamo detainee released and sent to another country so far this year.

The US Navy’s base at Guantanamo Bay, Cuba, held about 600 prisoners at its peak in 2003. With Al Sharbi’s transfer, it now holds 31 detainees, including 17 people considered eligible for transfer if a stable country can be found to accept them, the defence department said.

Another three Guantanamo inmates are eligible for review, while nine are facing charges under military commissions and two have been convicted in such commissions.

Two Pakistani brothers – Abdul, 55, and Mohammed Rabbani, 53 – were freed and returned home last month after being held at Guantanamo Bay for 20 decades.

Pakistani Senator Mushtaq Ahmed Khan, chairman of a human rights committee in the country’s upper house of parliament, said the men were innocent but imprisoned by the US for 21 years.

“There was no trial, no court proceedings, no charges against them. Congratulations on their release. Thank you Senate of Pakistan,” he wrote on Twitter at the time of their release.

The brothers were transferred to US custody after Pakistani officials arrested them in Karachi in 2002. The US accused the pair of helping al-Qaeda members with housing and other lower-level logistical support.

Human rights organisations have long called for the Guantanamo prison camp to be shut down. (Al Jazeera)

•PHOTO: The exterior of Camp Delta prison at the US Naval Base, Guantanamo Bay, Cuba. Guantanamo held about 600 prisoners at its peak in 2003 and still holds 31 detainees following the release of Saudi engineer Ghassan Al Sharbi after 21 years [File: Reuters]

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