Islamic State mass graves traced with thousands of bodies
At least 72 mass graves containing thousands of bodies have been uncovered as the territory held by the Islamic State group in Iraq and Syria is gradually clawed back.
In exclusive interviews, photos and research, Associated Press has documented and mapped 72 mass graves, in the most comprehensive survey so far, with many more expected to be uncovered.
In Syria, AP has obtained locations for 17 mass graves, including one with the bodies of hundreds of members of a single tribe all but exterminated when IS extremists took over their region.
For at least 16 of the Iraqi graves, most in territory too dangerous to excavate, officials do not even guess at the number of dead. In others, the estimates are based on memories of traumatised survivors, IS propaganda and what can be gleaned from a cursory look at the earth.
Estimates for the total number of victims range from 5,200 to more than 15,000.
Sinjar mountain is dotted with mass graves, some in territory taken back from IS after the group's onslaught against the Yazidi minority in August 2014, and others in a deadly no man's land that has yet to be secured.
IS made no attempt to hide its atrocities - in fact, it boasted of them - but proving what United Nations officials and others have described as a continuing genocide - and prosecuting those behind it - will be complicated as the graves deteriorate.
"We see clear evidence of the intent to destroy the Yazidi people," said Naomi Kikoler, who recently visited the region for the Holocaust Museum in Washington DC. "There's been virtually no effort to systematically document the crimes perpetrated, to preserve the evidence, and to ensure that mass graves are identified and protected."
Then there are the graves still out of reach. IS atrocities extend well outside the Yazidi region in northern Iraq.
Satellites offer the clearest look at massacres such as the one at Badoush prison in June 2014 that left 600 male inmates dead. A patch of scraped earth and tyre tracks show the probable killing site, according to exclusive photos obtained by imagery intelligence firm AllSource Analysis.
Of the 72 mass graves documented by AP, the smallest contains three bodies, while the largest is believed to hold thousands, but no-one knows for sure.
The sites include the northern flank of Sinjar mountain, where five grave sites ring a desert crossroads. It is here that the young men of Hardan village are buried, under thistles and piles of cracked earth. They were killed in the bloody IS offensive of August 2014.
Through his binoculars, Arkan Qassem watched it all from his village of Gurmiz, just up the slope from Hardan . He witnessed the militants set up checkpoints, preventing residents from leaving. Women and children were taken away.
Then the killings began. The first night, he saw the militants line up a group of handcuffed men in the headlights of a bulldozer at an intersection, less than half a mile down the slope from Gurmiz. They gunned the men down, then the bulldozer ploughed the earth over their bodies.
Over six days, Mr Qassem and his comrades watched helplessly as the fighters brought out three more groups of men - several dozen each, usually with hands bound - to the crossroads and killed them.
IS fighters have since been driven out of the area, and the 32-year-old has returned to his home.
Nearly every area freed from IS control has unmasked new mass graves, like one found by the sports stadium in the city of Ramadi. Many of the graves are easy enough to find, most covered with just a thin coating of earth.
"They don't even try to hide their crimes," said Sirwan Jalal, the director of Iraqi Kurdistan's agency in charge of mass graves. "They are beheading them, shooting them, running them over in cars, all kinds of killing techniques, and they don't even try to hide it."
No-one outside IS has seen the Iraqi ravine where hundreds of Shiite prison inmates were killed point blank and then torched. Satellite images of scraped dirt along the river point to its location, according to Steve Wood of AllSource. His analysts triangulated survivors' accounts and began to systematically search the desert according to their descriptions of that day, June 10 2014.
The inmates were separated out by religion, and Shiites were loaded on to trucks, driven for a few miles and forced to line up and count off, according to accounts by 15 survivors gathered by Human Rights Watch. Then they knelt along the edge of the crescent-shaped ravine, according to a report cited by AllSource.
The men survived by pretending to be dead.
Using their accounts and others, AllSource examined an image from July 17 2014 that appeared to show the location as described, between a main road and the railway outside Mosul. The bodies are believed to be packed tightly together, side by side in a space approximately the length of two football fields, in what the AllSource analysis described as a "sardine trench". Tyre tracks lead to and from the site.
Mr Wood said: "Ultimately there are many, many more sites across Iraq and Syria that have yet to be either forensically exhumed or be able to be detailed and there's quite a bit more research that needs to take place."
The key, he said, is having photos to indicate a grave's location taken soon after its creation.
Justice has been done in at least one IS mass killing - that of about 1,700 Iraqi soldiers who were forced to lie face-down in a ditch and then machine-gunned at Camp Speicher. On August 21, 36 men convicted over those killings were hanged at Iraq's Nasiriyah prison.