Islamic State forces in Iraq have abducted tens of thousands of men, women and children from areas around Mosul and are using them as "human shields" in the city as Iraqi government troops advance, the UN human rights office says.
The hardline Sunni militants killed at least 232 people on Wednesday, including 190 former Iraqi troops and 42 civilians who refused to obey their orders, UN human rights spokeswoman Ravina Shamdasani said.
"Credible reports suggest that ISIL has been forcing tens of thousands of people from their homes in sub-districts around Mosul and have forcibly relocated numbers of civilians inside the city itself since the operation began on the 17th of October to restore Iraqi government control over Mosul," Shamdasani told a briefing.
This was to "use them as human shields, to be able to keep them close to military installations...to try to frustrate the military operation against them," she said.
Nearly 8000 families, of roughly six people each, were abducted in sub-districts including Shura, she said.
"ISIL's depraved cowardly strategy is to attempt to use the presence of civilian hostages to render certain points, areas or military forces immune from military operations, effectively using tens of thousands of women, men and children as human shields," Shamdasani said.
"Many of those who refused to comply were shot on the spot," she said.
The reports, from people who have fled as well as aid groups, have been corroborated by the United Nations, she added.
Iranian-backed Iraqi Shi'ite paramilitary groups are about to launch an offensive on Islamic State positions west of Mosul, assisting in the military campaign to take back the city, a spokesman said on Friday.
UN High Commissioner for Human Rights Zeid Ra'ad al-Hussein has voiced deep concern at reports that some individuals in the areas south of Mosul have "embarked on revenge killings and have vowed on television that there would be 'eye-for-eye' revenge against those who sided with ISIL", Shamdasani said.
"Some people say that 'I saw this man coming, and he killed my father, so I couldn't resist, I had to exact revenge', she said.
Some villagers have been prevented from returning to their villages due to their perceived support of ISIL, she said.
Government screening is in place to check people fleeing Mosul but the process must be carried out in humane conditions respecting interNational Standards, Shamdasani said.