Mr Hague said the UK would work with EU partners to impose sanctions on those responsible to help bring an end to the violence.
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.
Almost all the former detainees interviewed by Human Rights Watch said they had been subjected to torture or witnessed the torture of others during their detention.
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Oliver Letwin MP, who was in charge of Brexit negotiations for two weeks, tells ITV News what he thinks will be easy and what will be hard.
Theresa May's decision to delay green-lighting Hinkley nuclear plant has put noses out of joint. But EDF is confident it will go ahead.
Highs of 23C at best in the afternoon sunshine but feeling cooler in the mornings and the evenings.