A new report by Human Rights Watch has identified that torture and atrocities in Syria are widespread, after carrying out more than 200 interviews since the beginning of anti-government demonstrations in the country in March last year.
Accounts from former detainees and defectors have identified the locations, agencies responsible, torture methods used and, in many cases, the commanders in charge of 27 detention facilities run by Syrian intelligence agencies.
The report, Torture Archipelago: Arbitrary Arrests, Torture and Enforced Disappearances in Syria's Underground Prisons since March 2011, includes maps locating detention centres, video accounts from former detainees and sketches of torture techniques described by people who witnessed or experienced torture in the facilities.
Interrogators, guards, and officers used a broad range of torture methods, including prolonged beatings, holding the detainees in painful stress positions for prolonged periods of time, the use of electricity, burning with acid and mock execution.
Human Rights Watch said the systematic patterns of ill-treatment and torture it had documented clearly pointed to a "state policy of torture and ill-treatment", which constituted "a crime against humanity".
Foreign Secretary William Hague said the report sounded a clear warning that there was "no hiding place" for those responsible for such crimes, adding the UK would work with EU partners to impose sanctions on those responsible to help bring an end to the violence.