BAGHDAD -- The stench of death drew Iraqi soldiers to the unsettled plot of land freshly liberated from Islamic State fighters.
When a bulldozer scraped the ground, bones poked from just beneath the surface, along with clothing scraps, garbage bags, human remains swarming with flies -- and even a child's stuffed animal.
About 100 bodies, many of them decapitated, are suspected to be buried in what is likely the latest mass grave left by the retreating jihadis, officials said.
Investigators on Tuesday began their probe of the site, located near an agricultural school in the town of Hamam al-Alil.
The gruesome discovery by troops advancing on militant-held Mosul fits a pattern in territory retaken from IS. The extremist group killed hundreds as it swept across northern and central parts of Iraq in 2014 and is believed to have carried out a brutal crackdown since the Oct. 17 start of an offensive to recapture the country's second-largest city.
"Investigators flew in this morning," said Haider Majeed, a Cabinet official in charge of mass grave inquiries. "They're conducting examinations to determine the cause of death."
It was unclear who the victims were, although the discovery of a stuffed animal raised the harrowing possibility that children may be among the dead.
In Geneva, the U.N. human rights office said it was investigating if the site was connected to reports about the alleged killing of police in the same area.
"We had reports that 50 former Iraqi police officers had been killed in a building outside Mosul," spokeswoman Ravina Shamdasani said. "This building was actually the same agricultural facility, agricultural college, that has been cited right now as the site of these mass graves."
She also said the U.N. had received information alleging that IS last week abducted at least 295 former security forces personnel from villages around the northwestern town of Tal Afar, as well as the western part of the village of Mawaly. The fate of the men is unknown.
About 30 sheikhs also reportedly were taken from the Sinjar district, with one report saying more than half of them were killed. The militants are alleged to have forcibly moved about 1,500 families to Mosul's airport from Hamam al-Alil, she added.
Iraqi troops and Kurdish peshmerga forces are converging on Mosul, although their deepest advance into an eastern sliver has stalled after militants counterattacked from populated areas.
To the northeast, about 13 kilometres (8 miles) from the city, the peshmerga continued their push on the town of Bashiqa, believed to be largely deserted except for dozens of IS fighters.
Mortar fire, automatic weapons and explosions echoed through the morning as a thick plume of smoke hung over parts of the town, obscuring the view of warplanes from the U.S.-led coalition.
More than 34,000 people have been displaced from Mosul, the U.N. said, with about three-fourths of them settled in camps; the rest are in host communities.
Food, water and medicine have been distributed to more than 41,000 displaced people and vulnerable residents who have fled the fighting, the U.N. reported.
Since the battle for Mosul reached the city itself Nov. 4, about 11,000 people have fled to the east, while some electricity and water supplies have been cut in eastern neighbourhoods.
IS extremists have rounded up thousands of civilians in and around Mosul and drawn them back into the dense, urban quarters of the city for use as human shields, the army and human rights groups alleged.
The militants have killed hundreds of Iraqis, mainly former members of the security forces, as they ready a fight to the death in the warrens of Mosul's residential streets and alleyways.
The Islamic State group has boasted of using mass killings to terrify opponents, often posting grisly photos and video of them online. As the fight intensifies, the militants are believed to be cracking down on anyone who could rise up against them, focusing on men with military training or past links to the security forces.
In Baghdad, meanwhile, bombings killed at least eight people and wounded 28 others, according to police and medical officials, who spoke on condition of anonymity because they were not authorized to brief reporters.
The capital has seen near-daily bombings since the Mosul operation began, but no large-scale attacks. The bombings are believed to have been carried out by IS, which has frequently targeted Iraq's security forces and Shiite majority.
