Evidence of capture and rituals is unearthed at a site near Mexico City.
Skeletons found at an archeological site show that Aztecs captured, sacrificed and partially ate several hundred people traveling with invading Spanish forces in 1520.
The condition of skulls and bones from the Tecuaque site east of Mexico City offers evidence that about 550 victims had their hearts ripped out by Aztec priests in ritual offerings, and were dismembered or had their bones boiled or scraped clean, experts say.
The findings support accounts of Aztecs capturing and killing a caravan led by Spanish conquistadors in revenge for the murder of Cacamatzin, king of the Aztec city of Texcoco. Experts said the discovery proved that some Aztecs did resist the conquistadors led by Hernan Cortes before they attacked the Aztec capital, Tenochtitlan, now Mexico City.
History books say many indigenous Mexicans initially welcomed the white-skinned horsemen, thinking they were returning gods, but turned against them once they tried to take over the Aztec seat of power in a conflict that ended in 1521.
"This is the first place that has so much evidence there was resistance to the conquest," said archeologist Enrique Martinez, director of the dig here. "It shows it wasn't all submission."
The prisoners were kept in cages for months while Aztec priests selected a few each day, cut out their hearts and offered them up to various Aztec gods, Martinez said.
"It was a continuous sacrifice over six months. While the prisoners were listening to their companions being sacrificed, the next ones were being selected," Martinez said, standing in his lab amid boxes of bones, some of young children.
The priests and town elders sometimes ate their victims' hearts or cooked flesh from their arms and legs, Martinez said. Knife cuts and even teeth marks on the bones show which ones had meat stripped off to be eaten, he said.
In Aztec times, the site was called Zultepec, a town of white-stucco temples and homes where 5,000 people grew maize and beans. Upon hearing of the massacre, Cortes renamed the town Tecuaque - "where people were eaten" in the indigenous Nahuatl language - and sent an army to wipe out its people.
When they heard the Spanish were coming, the Zultepec Aztecs threw their victims' possessions down wells, unwittingly preserving buttons and jewelry for archeologists.
"They hid all the evidence," Martinez said. "Thanks to that act, we have been allowed to discover a chapter we were unaware of in the conquest of Mexico."