

The inmates were separated out by religion, and Shiites were loaded onto 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.



"I was number 43. I heard them say '615,' and then one ISIS guy said, 'We're going to eat well tonight.' A man behind us asked, 'Are you ready?' Another person answered 'Yes,' and began shooting at us with a machine-gun. Then they all started to shoot us from behind, going down the row," according to the Human Rights Watch account of a survivor identified only as A.S.



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 end to end, in what the AllSource analysis described as a "sardine trench." Tire tracks lead to and from the site.



"There's actually earth that has been pushed over and actually moved to cover parts of the ravine. As we look across the entire ravine we only see that in this one location," said Wood. "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, Wood said, is having photos to indicate a grave's location taken soon after its creation.