The fall of Bashar al-Assad’s regime did not free all Syrian prisoners.
Al-Sina prison holds more than 5,000 prisoners in the Kurdish-controlled northeast of the country.
These prisoners, including some Britons, are suspected of being militants and supporters of the so-called Islamic State group. It is said that the majority were loyal to him until his last performance in 2019.
The BBC’s senior international correspondent, Orla Guerin, has a rare opportunity to visit a prison.