We've all heard of Otzi the Ice Man or whatever, reportedly the "world's oldest murder mystery". But try this shit on for size: In the neolithic age, tens of thousands of years ago, somewhere in middle-europe... Skeleton evidence suggests upwards of 60 killings occurred in a small settlement. Many men were killed, the very old (by caveman standards) and children were not spared. It was suggested that everyone was killed. Everyone, perhaps, except for a conspicuous lack of breeding-aged women, who either weren't killed in this event, or their bodies weren't left behind.
There was nothing to suggest that the village was burned, but there's not a lot of evidence of re-settlement after the massacre. This was not a conquest. Teethmarks are on the bones, suggesting animals got at them, and they were left unburied for quite some time. It's likely that another group found these bodies in an empty settlement and buried them long after it happened.
What happened here? Alternately, write a story from the perspective of the neolithic people who might have found them. (Or post your own writing prompts you don't have time for.)