The Pentagon repatriated a Tunisian detainee on Monday who had been held at Guantanamo Bay since the prison's opening, without ever being charged or tried at the war court, The New York Times reported.

Ridah Bin Saleh al Yazidi, 59, had been approved for transfer more than 10 years ago but had remained at the facility due to difficulties in securing his repatriation or resettlement.

He was secretly flown back to Tunisia, nearly a year after the Department of Defense informed Congress of an agreement to return him. No details were provided regarding the security arrangements for his transfer.

Al Yazidi’s release marked the fourth transfer in two weeks as part of a final push by the Biden administration to reduce the detainee population at the prison.

When Biden took office, 40 prisoners remained at Guantanamo; now, 26 detainees remain, with 14 approved for transfer, pending security and diplomatic arrangements.

Nine prisoners are either in pretrial proceedings or convicted of war crimes, which means the Biden administration is unlikely to fulfill President Obama’s goal of closing the facility. As the prison approaches its 24th year in January, its focus has reportedly shifted to conducting military trials, rather than detaining and interrogating prisoners as it did in its early years.

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Al Yazidi was the last of a dozen Tunisians once held at Guantanamo Bay, most of whom were captured in Afghanistan or Pakistan after the September 11 attacks and brought to the prison as terrorism suspects. He was one of the first detainees sent to Guantanamo on January 11, 2002, and became part of one of the most iconic images of the detention facility—photographed kneeling in a crude open-air compound at Camp X-Ray.

With his transfer, only one of the original 20 detainees remains at the prison: Ali Hamza al-Bahlul, who is serving a life sentence for conspiring to commit war crimes as a media advisor to Osama bin Laden.

According to a leaked 2007 prison assessment, al Yazidi was captured by Pakistani forces near the Afghanistan border in December 2001, part of a group of about 30 men who had reportedly fled the battle of Tora Bora. Some in the group were suspected of being bodyguards to bin Laden, making them key targets in the early efforts to locate the al-Qaeda leader.

The assessment described al Yazidi as a "dangerous detainee" who had been hostile to the Guantanamo guard force, with reports of him defacing a library book and throwing a cup of tea at a US soldier. However, by 2010, an Obama administration task force determined that al Yazidi could not be prosecuted for war crimes and should be eligible for release to another country with security assurances.

But al Yazidi's transfer was delayed for years. Ian Moss, who spent a decade at the State Department arranging detainee transfers, explained that al Yazidi remained at Guantanamo because Tunisia was considered either too dangerous or uninterested in taking him, and al Yazidi himself refused to meet with countries that might have resettled him.

"He could have been gone a while ago but for Tunisian foot-dragging," Moss said.

The New York Times mentioned that little is known about al Yazidi beyond information from leaked US intelligence documents, which state that he lived in Italy during the 1980s and 1990s and was arrested for involvement in illegal drugs.

In 1999, he moved to Afghanistan, where he reportedly attended a militant training camp. It is unclear what family members await him in Tunisia, and it appears he has not had contact with a lawyer in nearly 20 years, the report noted.

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