• The UN human rights chief cites reports that civilians have been shot dead by ISIS.
• Nearly 30 ISIS militants have taken over a building in southern Kirkuk and fired on security forces.
• Twelve people were killed in a separate ISIS attack in Dibis.
• Iraqi-led forces have recaptured at least 100 square kilometers (39 square miles) of territory, CNN analysis shows.
UN had expressed concern
Zeid Ra'ad Al Hussein, UN High Commissioner for Human Rights, said his office had evidence of several instances since Monday where ISIS forced civilians to leave their homes in outlying villages and head to Mosul. It also had received reports that civilians suspected of disloyalty had been shot dead.
"We are gravely worried by reports that (ISIS) is using civilians in and around Mosul as human shields as the Iraqi forces advance, keeping civilians close to their offices or places where fighters are located, which may result in civilian casualties," Zeid said.
"There is a grave danger that (ISIS) fighters will not only use such vulnerable people as human shields but may opt to kill them rather than see them liberated," he said.
His office is examining reports that ISIS shot dead at least 40 civilians in a village outside Mosul.
Any ISIS fighters who are captured or surrendered "should be held accountable in accordance with the law for any crimes they have committed," he said.