"Yezidi [Yazidi] fighters in Iraq allegedly forcibly disappeared and killed 52 civilians from the Imteywit tribe in June 2017," HRW said in a release, adding that Yazidis executed men, women and children from eight families as they fled fighting between Daesh west of Mosul on June 4.
Human Rights Watch said its findings were based on interviews with relatives of the victims and Yazidi community leaders, as well as other witnesses to the attack, which was apparently carried out in revenge for Daesh's abuses against Yazidi women.
A member of the PMF intelligence services told Human Rights Watch that he was sent to Sinjar to investigate the allegations, the release said.
With help from local Yazidis, the investigator located a cluster of four mass graves in Qabusiye, which he visited on December 5.
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The investigator saw the bones and skulls of at least four children, tufts of women’s hair, and women’s and children’s shoes and bracelets in the vicinity of the graves, HRW said.
HRW calls the executions war crimes and called on Iraqi authorities to hold the perpetrators accountable.
"Iraqi criminal justice authorities should investigate alleged criminal offenses by all parties to the conflict in a prompt, transparent, and effective manner, up to the highest levels of responsibility. Those found criminally responsible should be appropriately prosecuted," HRW said.
In 2014, Daesh killed thousands of Yazidis and forced abducted women to become wives or slaves of Daesh fighters in a campaign that was labeled genocide by the United Nations.