The case has been brought to the ICJ by both Canada and the Netherlands. They are calling for immediate action to stop the mistreatment of people currently in detention.

Professor René Lefeber, representing the Netherlands, said: “Every day counts. Persons in Syria who are currently detained or at risk of being detained cannot afford to wait any longer.”

While Damascus chose to abstain from the initial day of hearings, it has previously categorised the case as “disinformation and lies” and argued that the claims “lack the slightest degree of credibility”.

Professor Lefeber presented testimony from those detained, including incidents of gang rapes, mutilation, and a “standardised” method of punishment where individuals are forced into a car tyre position followed by a “severe beating”.

Canada and the Netherlands have called on the ICJ to “urgently” insist that Syria ends all torture and unwarranted detention. They are also urging Syria to grant external inspectors access to prisons and offer families information regarding their detained relatives.

While a final verdict from the ICJ can span years, expedited “provisional measures” might be made within weeks and are legally binding.

Former prisoner and now activist, Ahmad Helmi, said: “I was in prison in Syria for three years and I know for sure that torture is happening around the clock. It doesn’t happen only for interrogation. Sometimes it happens for fun. Just because they feel they enjoy impunity, they can do whatever they want.”

Balkees Jarrah, of Human Rights Watch, said that the ICJ’s intervention was crucial “to prevent further abuses against Syrians, who continue to suffer under nightmarish conditions and whose lives are in serious jeopardy”.

Despite having little expectation that Syria will honour any ICJ verdict, Mr Helmi said: “We are not talking about a local court somewhere. It’s not me saying torture is happening. This will be the ICJ saying that torture is happening.”

He added: “And whoever wants to renormalise the Syrian regime, they will have this tag on their forehead that you are normalising with a state that is torturing people around the clock.”