HARDAN, Iraq - After he fled from this northern Iraqi hamlet four months ago, Hayder Khalef got panicked phone calls from his relatives who had remained behind. They were at that moment being led by Islamic State group gunmen toward a checkpoint on the edge of town.

"If you don't hear from us, you'll find our bodies near the checkpoint," Khalef said they told him in the calls.

He is back in his hometown for the first time since, after Iraqi Kurdish fighters last week drove out the extremists holding the village. Khalef and a few other residents who escaped followed the Kurds in, hoping to discover what happened to hundreds of their relatives and neighbors who vanished after the jihadis overran Hardan in early August.

They fear they know where they are: four mounds of recently dug-up earth. The sites have not yet been excavated, but Khalef and others are convinced they are mass graves, possibly holding dozens of dead. From the loose top soil, they and Kurdish fighters pulled out pieces of clothing as an Associated Press reporter watched.

At one point, they tugged on the elastic waistband of pants visible in the dirt - and it seemed a body was still wearing them. The ground bulged with the weight of a body being pulled up with the waistband. They stopped pulling, fearing booby traps, before a body could be clearly seen. But an ID card and some prayer beads fell out of the pants pocket - the ID of a 44-year-old man named Khero Khudeda Rufo. One returning resident, Khaled Wase, recognized the name as a neighbor who is among the missing.

There is no way to definitively say the mounds are graves or know how many bodies are in them until they are dug up. The Kurds have no plan to do so immediately, though they have cordoned off the four sites with tape. Fighting continues with Islamic State militants not far away, and the situation is too unstable to deal with searching for bodies. But Wase and Khalef say they are certain their loved ones are buried in the sites.

"They are all from my village and some of my cousins were arrested [by the militants] and may be here," Wase said, referring to the earth mounds. "My relatives are there along with all those from my village." Wase and Khalef estimate that 530 people are missing from Hardan, out of an original population of about 200 families, and he believes most were killed by the militants.