A Yemeni man on May 9, 2017, describes the detention of his son by Yemeni forces allied to the United Arab Emirates who raided his home in the southern village of Abr Lasloum. Fearing reprisals, he asked that his identity be obscured. (Maad El Zikry/AP)

The United Arab Emirates and allied security forces maintain a secret network of prisons in Yemen where dozens and perhaps hundreds of people are detained, routinely abused and in some cases severely tortured, according to separate reports released Thursday by Human Rights Watch and the Associated Press. 

The investigation by the AP also found that forces from the United States, a close counterterrorism ally to the UAE, had participated in interrogations of prisoners in Yemen. American forces had been “yards” away from a facility where torture took place, one Yemeni security officer told the news agency.  

The UAE is part of a Saudi-led military coalition fighting in Yemen against Houthi rebels and their allies, with the goal of restoring the government of ousted Yemeni President Abed Rabbo Mansour Hadi. The conflict has devastated Yemen, the Arab world’s most impoverished country, and killed more than 10,000 people, according to the United Nations. 

The government of the UAE denied the existence of a clandestine prison network, telling the AP that “there are no secret detention centers, and no torture of prisoners is done during interrogations.” 

A deserted cell in the public section of Aden Central Prison is shown in this May 9, 2017, photo in Aden, Yemen. A separate, closed wing is run by Yemeni allies of the United Arab Emirates, part of a network of secret prisons in southern Yemen into which hundreds of people have disappeared after being detained in the hunt for al-Qaeda militants over the past year. (Maad El Zikry/AP)

Asked about allegations raised in the AP article, Marine Corps Maj. Adrian Rankine-Galloway, a Pentagon spokesman, said in an email that “as a matter of policy we do not discuss the details of bilateral intelligence arrangements with partner nations.”  

“Under no circumstances do DoD personnel participate in violations of human rights,” he added, referring to the Department of Defense. “Additionally, as a matter of policy, they are required to report any observation of human rights violations through standard reporting procedures.”

The UAE has taken a leading role in the war, landing troops in southern Yemen and participating in the air campaign against the rebels while also pursuing relief and reconstruction projects. Emirati officials have portrayed the country’s foray into Yemen as part of its increasingly assertive counterterrorism efforts in the region. 

The reports released Thursday added new, troubling details to that effort and to the shadowy conflict that pits coalition forces and their Yemeni allies against extremist groups such as al-Qaeda in southern Yemen.

In its report, Human Rights Watch said it documented the cases of at least 38 people detained or arrested by Yemeni forces that are financed, armed or trained by the UAE. Some of the detainees were “abused or tortured inside detention facilities, most often through heavy beatings with officers using their fists, their guns or metal objects,” the group said. “Others mentioned electric shocks, forced nudity, threats to the detainees or their family members, and caning on the feet.”

Witnesses told the AP of a torture method known as the “grill.” Victims were “tied to a spit like a roast and spun in a circle of fire.” That method and others were used at a detention complex at an airport in the southern city of Mukalla — one of at least 18 secret prisons in southern Yemen documented by the AP and run by the UAE or its allied forces at “military bases, ports, an airport, private villas and even a nightclub.” 

Yemeni businessman Ali Awad Habib recounts the torment he suffered in prison, where he said he was beaten with wires and wooden clubs and given electrical shocks, in this May 8, 2017, photo in Aden, Yemen. (Maad El Zikry/AP)

Thomas Gibbons-Neff in Washington contributed to this report.