The US Department of Defense announced on Tuesday that a Kenyan prisoner had been released from Guantanamo Bay, the US military prison infamous for inhumane torture at a US base in Cuba.

Now, only 29 people remain imprisoned at Guantánamo, mostly convicted or accused of extremist terrorism – among them Khalid Sheikh Mohammed, believed to be the mastermind of the September 11, 2001 attacks on New York and the Pentagon.

According to a report by the Washington Post, Mohammed Abdul Malik Bazzabu was arrested in 2007 and accused of belonging to the East African branch of the jihadist organization al-Qaeda.

Bajabu joined Kenya after US authorities determined his imprisonment was no longer “necessary to prevent a continuing significant threat to national security”, according to a press release released by the Pentagon.

Of the 29 detainees at Guantanamo Bay, 15 are eligible for transfers, three are for consideration for possible release, seven are facing various charges and four have been convicted, the US Department of Defense statement listed.

The Guantanamo Bay prison, where up to 800 alleged Al-Qaeda members have been held, has tarnished the US’s image internationally for years.

Outgoing President Joe Biden, like Barack Obama before him, has promised to close it during his term.