Keep your friends close and your enemies closer?

Researchers working in Mexico have unearthed evidence that ancient Maya in the region dismembered and decapitated some of their prisoners, dumping them in a mass grave that was hidden for 1,400 years.

The discovery resulted from a five-year investigation led by anthropologists from the University of Bonn in Germany, according to a written statement released by the university. Excavating the Maya city of Uxul in Campeche, Mexico, archaeologists discovered the well-preserved remains of 24 people -- all of whom appeared to have met a very violent end -- in an artificial cave.

"The observed hatchet marks on the cervical vertebra are a clear indication of decapitation," archaeologist Nicolaus Seefeld, the researcher who discovered the remains, said in the statement. Other bones showed evidence of blows from sharp weapons, including cudgels and hatchets.

In an email to The Huffington Post, Seefeld said the remains were found "in an extraordinarily good state of preservation" because the grave had been covered with gravel and sealed with clay. This was helpful to researchers because while such violence has been depicted in Maya artwork, there has been only one other documented instance of a similar mass killing carried out by the pre-Hispanic culture, Seefeld told HuffPost.

"In fact, the explicit traces of a violent killing make this finding so remarkable," he said. "Apart from that the analysis of the bone material and teeth did already provide us with interesting insights into the life's reality of Uxul's past inhabitants."

A mysterious but culturally impressive ancient culture, the Maya lived in parts of Mexico and Central America from about 1800 B.C. until they made contact with Spanish conquistadors in 1502, according to National Geographic. However, researchers are still attempting to discern possible motivations for the gruesome acts that unfolded in Uxul.

"The killing and chopping of victims may have been either a ritual act (probably a kind of sacrifice in an extremely dramatic situation for the community), or a gruesome public act of extermination," Dr. Nikolai Grube, one of the leaders of the research team, said in an email to The Huffington Post. "It is possible that the Maya wanted to wipe out a particular family, or a group of captives, and that this massacre was perpetrated at such a scale and in a central area of the city as a kind of political statement."

Grube added that researchers plan to use isotope analysis of the dismembered remains in order to learn more about the identity of the victims, which may in turn help experts understand the killings.

LOOK:

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  • This image shows an excerpt of the mass grave during the excavation process in the late April of 2013. As becomes obvious in this picture, the visible skulls, lower jaws and ribs are no longer in their natural anatomical articulation.

  • This image shows the lower jaw from one of the buried individuals, featuring a jade incrustation in the lower right incisor. Due to the scarcity of jade and the high popularity it had in the classic Maya culture, such incrustations are usually considered as strong indicators of a high social status of the respective individual.

  • This is a detailed image of an unhealed skull fracture on the forehead of another individual. The cross-shaped form of the structure is very characteristic for blunt force trauma from an object such as a cudgel.

  • This image depicts the left side of another individual's skull whose upper part has been entirely chopped off. The fine nature of the breaking edge shows that the destruction of this skull did not occur after its deposition, but that it was instead caused by a sharp object (in the society of the Classic Maya presumably a stone-axe).