After interviewing more than 200 former detainees, Human Rights Watch (HRW) has been able to map out 27 of the Syrian government's detention centres.
From the interviews, HRW has chronicled the Assad regime's torture methods - beatings, stress positions, electrocution, acid and more.
The majority of those detained by Assad's security forces are between 18 and 35 years old, although they documented children as young as 10 and 11 being detained along with women and the elderly.
HRW says the evidence from their interviews points to a state-imposed policy of arbitrary detention and torture. The organisation has also called for Syria to be referred to the International Criminal Court (ICC).
