A UN envoy has said more than 50 mass graves have been discovered in areas once held by the Islamic State (Isis) as evidence of genocide mounts against the terror group. As Isis (Daesh) concede land in Iraq human remains from thousands of men, women and children have been discovered buried in shallow graves.

The extremists massacred Yazidis, Sunni and Shia Muslims, Kurds and Iraqi troops as they carved their self-declared caliphate in Syria and Iraq out of blood. Mass graves have been found near Mount Sinjar in northern Iraq, near Anbar in western Iraq and in Tikrit in northern Iraq.

As IS lose territory to advancing troops and US-led western air strikes, more evidence of genocide and crimes against humanity are emerging. In the latest discovery, on 19 April in the city of Ramadi, three graves containing remains of 40 people were found in a football field.

According to official figures, more than 10 million people in the war-torn nation need international aid. UN special representative Jan Kubis told the UN Security Council that a quarter of the $861m (£596m) requested for aid to Iraqis in 2016 had been delivered.

Kubis told the UN Security Council that it was "evidence of heinous crimes" and that the international community should "take steps to ensure the accountability" the BBC reported. "I condemn in the strongest possible terms the continued killings, kidnapping, rape and torture of Iraqis by ISIL (Islamic State), which may constitute crimes against humanity, war crimes and even genocide."

The UN envoy added that despite "notable and consistent progress" against IS, it was still "a formidable and determined enemy that constantly adjusts its tactics and attack patterns". Kubis called for addressing the "the root causes of violent extremism", saying that the jihadists would not be defeated by just a military.

In December 2015, Iraqi forces took back Ramadi with one mass grave revealing dozens of skeletons belonging to tribesmen, Iraqi soldiers, women and people from the minority Yazidi sect. It had been held by the militants since May of the same year.

At least 16 of the mass graves were discovered in Sinjar in northern Iraq. Kurdish forces have found bones, hair and personal effects with one of the graves said to contain the bodies of more than 70 elderly female Yazidis, while another is said to contain 60 bodies of women and children east of the town in the Yazidi homeland.

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