The BBC has been given access to detention facilities on former United Arab Emirates military bases in Yemen, confirming long-standing allegations of a network of secret prisons run by the UAE and forces allied to it in Yemen's decade-long civil war. One former detainee told the BBC he had been beaten and sexually abused at one of the sites. We saw cells at two bases in the south of the country, including shipping containers with names - apparently of detainees - and dates scratched into the sides. The UAE did not respond to our request for comment, but has previously denied similar allegations. Until recently, the Yemeni government, which is backed by Saudi Arabia, was allied with the UAE against the Houthi rebel movement which controls north-west Yemen. But the alliance between Yemen's two Gulf state partners has fractured. UAE forces pulled out of Yemen in early January and Yemeni government forces and groups allied to them have retaken large swathes of the south from separatists backed by the UAE. This includes the port of Mukalla, where we landed in a Saudi military plane and were taken to visit the former UAE military bases in the Al-Dhaba Oil Export Area. It has been almost impossible for international journalists to get visas to report from Yemen in recent years, but the government invited reporters to view the two sites, accompanied by Yemen's Information Minister Moammar al-Eryani. What we saw was consistent with accounts we have gathered independently, both in our previous reporting and also interviews conducted in Yemen, separately from the government-run site visit. At one site, there were about 10 shipping containers, their interiors painted black, with little ventilation. Messages on the walls appeared to mark the dates detainees said they were brought in, or to count the number of days they had been held. Several were dated as recently as December 2025. Human rights groups have documented testimony describing such facilities for years. Yemeni lawyer Huda al-Sarari has been gathering accounts. The BBC independently attended a meeting she organised, where about 70 people were present who said they had been held in Mukalla, as well as the families of another 30 who they said their relatives were still in detention. Several former detainees told us that each shipping container could hold up to 60 men at a time. They said prisoners were blindfolded, bound at the wrists and forced to remain sitting upright at all hours. There was no space to lie down, one former prisoner told the BBC. If someone collapsed, the others had to hold him up. The man also told the BBC he was beaten for three days after his arrest, with interrogators demanding he confess to being a member of al-Qaeda - an accusation he denies. They told me if I didn't admit it, I would be sent to 'Guantanamo,' he said, referring to the US military detention centre at Guantanamo Bay in Cuba. He said he was held there for a year and a half, beaten daily and abused. They didn't even feed us properly, he said. If you wanted the toilet, they took you once. Sometimes you were so desperate you did it on yourself. He says his captors included Emirati soldiers as well as Yemeni fighters: All types of torture - when we were interrogated it was the worst. They even sexually abused us and said they would bring in the 'doctor.' This so-called doctor was Emirati. He beat us and told the Yemeni soldiers to beat us too. I tried to kill myself multiple times to make it end. The UAE was leading a counter-terror campaign in southern Yemen, but human rights groups say thousands of people were detained in crackdowns on political activists and critics. A mother told us her son was detained as a teenager and has been held for nine years. My son was an athlete, she said. He had just come back from competing abroad. That day he went to the gym and never came back. She alleged that in the prison at the Emirati-run base, her teenage son was electrocuted, doused with ice-cold water and sexually abused multiple times. She says she attended a hearing in which her son's accusers played a recording of him apparently confessing. You can hear him being beaten in the background and told what to say, she said. My son is not a terrorist. You have robbed him of the best years of his life. Over the past decade, human rights groups and media organisations - including the BBC and Associated Press - have documented allegations of arbitrary detention, enforced disappearance and torture in detention centres run by the UAE and its allies. Human Rights Watch said in 2017 it had gathered testimonies of detainees held without charge or judicial oversight in unofficial facilities, and subjected to beatings, electric shocks and other forms of ill treatment. The UAE denied these allegations when they were made. Families of detainees told the BBC they had repeatedly raised concerns with Yemeni authorities. They believe it would have been impossible for the UAE and its allies to run a detention network without the Yemeni government and its Saudi backers knowing about it. The information minister, Eryani, said: We weren't able to access locations that were under UAE control until now. When we liberated them we discovered these prisons… we had been told by many victims that they existed but we didn't believe it was true. His government's decision to give access to international media comes as the rift between Saudi Arabia and the UAE is widening. Their long-strained relationship deteriorated in December when UAE-backed southern separatists, the Southern Transition Council (STC), seized territory controlled by government forces in two western provinces. Saudi Arabia then carried out a strike on what it said was a shipment of weapons from the UAE to the STC in Mukalla, and backed a demand from Yemen's presidential council for Emirati forces to leave the country immediately. The UAE denied that the shipment had contained weapons and also Saudi allegations that it was behind the STC's recent military campaign.