Al-Jazeera met with Turkish citizen Riad Ullar to talk about the story of the 21 years he spent in the prisons of the Syrian regime.
Riad traveled to Syria in 1996 to learn the Arabic language, and at that time he was a 19-year-old student.
A year later, the Syrian authorities arrested him for reasons that he said were security, and he remained forcibly disappeared in the Syrian regime's prisons for 15 years.
A Syrian court sentenced him to death, then commuted the sentence to life imprisonment, and he was released in 2017.