Washington, DC, Asharq Al-Awsat—The authors of a UN report accusing the Islamic State of Iraq and Syria (ISIS) of committing war crimes and crimes against humanity in Syria called on the international community on Friday to bring the group’s leadership to justice.

Rolando Gómez from the UN human rights commission told Asharq Al-Awsat the report recommended activating mechanisms to bring the commanders of ISIS, including leader and self-styled “caliph” Abu Bakr Al-Baghdadi—whom the report said wielded “absolute power” over the group—before an international tribunal such as the International Criminal Court (ICC) in the Hague.

Paulo Sérgio Pinheiro, a Brazilian diplomat and member of the team that drafted the report, told reporters on Friday ISIS’s commanders had “acted willfully” in perpetrating the crimes, for which they were “individually criminally responsible.”

The 70-page report, released on Friday, based its findings on interviews with over 300 victims and eyewitnesses, as well as evidence from documents, photographs and video footage released by the group itself.

It said the group was committing “egregious violations of binding international humanitarian law and the war crime of murder on a massive scale” in areas under its control in Syria, including the “mass killings of captured fighters and civilians.”

Lama Fakih, Syria and Lebanon researcher at Human Rights Watch, told Asharq Al-Awsat the extensive first-hand and eyewitness reports collected by the UN document would form a credible body evidence that could be presented to an international court such as the ICC.

She added that the report also recommended bringing figures from the Syrian regime of President Bashar Al-Assad to justice, also for war crimes and crimes against humanity.

The UN Security Council already proposed such a move in May, but it was vetoed by members Russia and China.

Some of ISIS’s crimes documented in the report included mass shootings, crucifying and beheading civilians, stoning women, recruiting child soldiers, forcing minorities to convert to Islam, as well as taking women as slaves and forcing them to bear children to the group’s fighters.

The report also found that the group was depriving food and medical aid to around 600,000 people in northern areas of Syria under its control.

Meanwhile, the UK-based Syrian Observatory for Human Rights—which monitors the conflict in Syria through a network of observers on the ground—said in press release on Friday ISIS had crucified and beheaded a member of the group for stealing money from “state coffers” in the city of Mayadin in the eastern Deir Ezzor province.

A photograph posted by the Observatory, purportedly of the man, showed him apparently crucified, with his head at his feet.

A sign attached to his torso said his death had been order by “Amir Al-Mu’mineen” (the Commander of the Faithful), a traditional alternative moniker for “caliph,” and which ISIS now uses to refer to its leader Baghdadi.