GENEVA - UN human rights chief Navi Pillay said on Monday a ruthless campaign of "ethnic and religious cleansing" by Islamic State jihadists in Iraq amounted to a crime against humanity.
She said their reign of terror against non-Arab ethnic groups and non-Sunni Muslims alike involved targeted killings, forced conversions, abductions, trafficking, slavery, sexual abuse, and destruction of holy and cultural sites.
"They are systematically targeting men, women and children based on their ethnic, religious or sectarian affiliation and are ruthlessly carrying out widespread ethnic and religious cleansing in the areas under their control," Pillay said in a statement.
"Such persecution would amount to crimes against humanity," she added.
The jihadists, who already occupied parts of Syria, launched an offensive in Iraq in June and rapidly seized much of its Sunni heartland.
Previously known as the Islamic State in Iraq and the Levant (ISIL), the jihadists rebranded themselves as the Islamic State after declaring a "caliphate" in a region straddling the Iraq-Syria border.
"Grave, horrific human rights violations are being committed daily by ISIL and associated armed groups," Pillay said.
Taken into slavery
Minority groups targeted include Christians, Yazidi, Shabaks, Turkomen, Kakae and Sabaeans, she said.
In the Nineveh region of northern Iraq, hundreds of Yazidi were reported killed and some 2,500 kidnapped at the beginning of August.
Those who agreed to convert to Islam were being held under jihadist guard. Among those who refused, the men were reportedly executed and the women and children taken into slavery, she said.
In the Sinjar region, the jihadists killed and abducted hundreds of Yazidi on August 15, she said, warning that residents of besieged villages remained at serious risk.
At least 13,000 members of the Shia Turkmen community in the Salah al-Din region -- among them 10,000 women and children -- have been besieged since mid-June, she said.
They face harsh living conditions with severe food and water shortages, and a complete absence of medical care, as fears of a massacre mount.
Pillay also condemned the forced recruitment of boys aged 15 and above, and their reported deployment of such youths as human shields on the front line.
In addition, she said the United Nations had verified reports of a massacre of up to 670 detainees by the jihadists after they overran a prison in the northern city of Mosul on June 10.
Many of the hundreds of thousands of people who have fled the jihadist onslaught have found a haven in Iraq's autonomous Kurdistan region, whose forces are trying to push back the Islamist fighters.
The United Nations last week launched a massive operation to send desperately needed aid into the region.
Pillay called on local authorities and the international community to "take all necessary measures and spare no effort to protect members of ethnic and religious communities, who are particularly vulnerable, and to secure their return to their places of origin in safety and dignity".
A UN watchdog on Monday urged the 47 nations that make up the UN Human Rights Council to hold an emergency session on the crisis.
The UN Committee for the Elimination of Racial Discrimination also said it was time for the UN Security Council to deploy a "peace force" to create a "safe zone" around Nineveh.