Archaeologists have discovered seven skeletons in a remote New Mexico canyon bearing testimony of a brutal massacre.
The massacre may have been part of an ancient campaign of genocide, they have said.
The victims-five adults, one child, and one infant-were members of an obscure native culture known as the Gallina, which occupied a small region of northwestern New Mexico around A.D. 1100. But the culture vanished around 1275, when the last of its members either left the region or were probably annihilated.
Tony Largaespada, an archaeologist with the US Forest Service who made the discovery in 2005, said the newfound skeletons could provide crucial clues to the people's mysterious fate, since scarcely more than a hundred Gallina remains have ever been found.
"Almost all of [the Gallina ever found] were murdered. [Someone] was just killing them, case after case, every single time," he said.
Greg Nelson, a physical anthropologist at the University of Oregon, who studied the newly unearthed skeletons, said they portrayed a "macabre picture of violence inflicted on both sexes and all age groups".
"It's pretty obvious that they were killed-they're people who were wiped out," he said.
The skeletons found revealed fractured skulls, broken forearms, jaws, thighbones, pelvis and ribs. One bore cut marks on the upper arm suggesting violent blows from an axe. The child, about two years old, had had its skull crushed.
Among the other peculiarities of the murder scene was the arrangement of two of the bodies.
The victims, an adult male and female, were found face down and doubled over, their heads snapped back so far that their skulls rested between their shoulder blades.
According to Nelson, their bodies may have been deliberately posed, or the victims may have been crouching in defence when their necks were broken.
Another strange thing was that none of the seven dead appeared to have been buried, suggesting that the group was struck by a swift attack.
"Normally when you bury people, you extend them, you flex them, you do these kinds of things-you don't bury them on their knees with their heads snapped back. So right away you know something screwy is going on," Nelson said.
Other intriguing evidence, the researchers said, included what appeared to be the ruins of a burned pit house, or dugout dwelling, nearby.
"Why these [victims] were outside the house is kind of a mystery. Usually [attackers] threw [Gallina victims] in their houses and burned the houses on top of them. That's the case with 90 percent of them. But in this particular case they were thrown in a pile outside the house. ... More than likely there are others [nearby]," said Largaespada.
According to the two researchers, though the findings are grimly consistent with previous reports from other Gallina sites, the new skeletons offer tantalizing signs of how unique the culture may have been.
But they are unsure whether the group was plagued by violent conflicts with neighbouring cultures.
"We just don't know right now. The evidence indicates that somebody was going through and killing them. Why and to what extent? We're not sure," National Geographic quoted Nelson as saying.
