The report is based on an investigation by the UN Human Rights Office, following a request from the UN Human Rights Council in September last year, at the initiative of the Iraqi government.
It said the UN Human Rights Council should urge the UN Security Council to address, "in the strongest terms, information that points to genocide, crimes against humanity and war crimes," and to consider referring the situation in Iraq to the International Criminal Court.
The report also highlights violations allegedly carried out by the Iraqi Security Forces and associated militia groups, including killings, torture and abductions which may constitute war crimes. It called on the Iraqi government to "investigate all crimes outlined in the report and bring the perpetrators to justice". The report also urged Baghdad to "become a party to the Rome Statute of the International Criminal Court and ensure that the international crimes defined in that Statute are criminalised under domestic law".
The bulk of the report nevertheless focuses on atrocities committed by ISIL. It documents a wide range of violations against numerous ethnic and religious groups in Iraq, some of which, it says, may amount to genocide. Documented abuses by ISIL include killings, torture, rape and sexual slavery, forced religious conversions and the conscription of children.
It cites targeted killings of hundreds of Yezidi men and boys in the Ninewa plains last August. "In numerous Yezidi villages, the population was rounded up," says the report. "Men and boys over the age of 14 were separated from women and girls. The men were then led away and shot by ISIL, while the women were abducted as the 'spoils of war.' (…) Witnesses heard girls – as young as six and nine years old – screaming for help as they were raped in a house used by ISIL fighters."
ISIL also meted out brutal treatment to other ethnic groups, the report says, including Christians, Kaka'e, Kurds, Sabea-Mandeans, Shi'a and Turkmen.