Outside the fence at Guantánamo Bay prison.

An update about the release has been added at the end of this story.

The Obama administration has found a place for 15 of the 76 remaining detainees held at the Guantánamo Bay military prison in Cuba. Their release to an unnamed nation (likely the United Arab Emirates, which has previously accepted detainees from the prison), will be announced Monday afternoon. The president released 10 Yemeni detainees to Oman in January and nine others to Saudi Arabia in April. Spencer Ackerman at The Guardian reports:

The transfer, expected to be officially announced by the Pentagon on Monday afternoon, brings the Guantánamo detainee population down to 61. All 15 detainees were said to on their way to the same nation, believed to be the United Arab Emirates, which has accepted former Guantánamo detainees in the past. Some of the 15 detainees were cleared for transfer out of Guantánamo by a 2010 multi-agency review, while others were deemed to pose a negligible security threat by a quasi-parole board which Obama established to expedite his long-pledged closure of Guantánamo Bay, according to a US official who spoke on condition of anonymity ahead of the official announcement.

The prisoners were captured overseas after the United States invaded Afghanistan and later Iraq following the Sept. 11, 2001, attacks on New York and Washington, D.C. Some could not be connected to terrorist acts or groups, and one who was cleared for release in January has been held for 13 years even though he was thought to be someone else with high-level connections to al-Qaida leaders.

Guantánamo has become synonymous around the world (and among U.S. critics) with torture and other violations of human rights. The George W. Bush administration’s decision to set up the prison—on land grabbed from Cuba by the United States in 1901 and forcibly leased since 1903—was predicated on the idea that neither international nor U.S. law would apply to the prisoners.

President Barack Obama vowed on his second day of office to shut down the prison within a year. But Congress—not just Republicans but some Democrats as well—kept that from happening. This was, in part, because 50 or more of the detainees held there since 2002 were considered too dangerous to release and would therefore have to be held at prisons in the United States.