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.
