Displaced families travel to positions held by Iraqi security forces in southern Mosul on March 11. On Thursday, the United Nations said it received reports indicating the Islamic State killed more than 231 civilians attempting to flee west Mosul. File Photo by Omar al-Hayali/EPA

June 8 (UPI) -- The Office of the United Nations High Commissioner for Human Rights said Thursday it has received credible reports indicating the Islamic State has recently killed more than 231 civilians attempting to flee west Mosul.

The office of the high commissioner, known as the OHCHR, said the Islamic State, also known as ISIL, ISIS and Daesh, killed the Iraqi civilians in separate days.


"The U.N. Human Rights Office has been documenting ISIL's use of civilians as human shields and its slaughter of those attempting to flee since the start of the Mosul operation, but recent reports indicate a significant escalation in such killings," the OHCHR said in a statement.

On May 26, the Islamic State fatally shot 27 civilians, including 14 women and five children, trying to flee west Mosul's al-Shifa neighborhood, the OHCHR said. The agency believes neighbors buried the victims later.

On June 1, the Islamic State fatally shot at least 163 men, women and children next to a Pepsi factory, the OHCHR said. The agency believes the civilians were fleeing fierce fighting between the Islamic State and Iraqi security forces

"The bodies of those who died were reportedly left on the street for several days following the killings. In addition to those who died, an undetermined number of civilians went missing," the OHCHR said in a statement.

On Saturday, the Islamic State fatally shot at least 41 civilians, also in al-Shifa, as they attempted to flee to locations secured by Iraqi forces.

Iraq launched its military offensive to retake western Mosul from the Islamic State on Feb. 19. The offensive to retake Mosul began Oct. 17, led by Iraqi security forces and aided by the Kurdish Peshmerga, a Shiite-led militia, and the U.S.-led international coalition. Iraq captured east Mosul in late January.

Though Iraqi officials have repeatedly said they are close to fully capturing west Mosul, they have yet to declare victory against the Islamic State in what would be the most significant win against the militant Islamist group.

"Shooting children as they try to run to safety with their families – there are no words of condemnation strong enough for such despicable acts," U.N. High Commissioner for Human Rights Zeid Ra'ad Al Hussein said in a statement. "I call on the Iraqi authorities to ensure that those who are responsible for these horrors are held accountable and brought to justice in line with international human rights laws and standards. The victims of such terrible crimes must not be forgotten."

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The OHCHR also said recent airstrikes in IS-held areas in west Mosul killed up to 80 civilians. The agency said it is seeking more information into the incident.