MEXICO CITY (AP) — Archaeologists in Mexico say they have found an unprecedented human burial in which the skeleton of a young woman was found near Mexico City's Templo Mayor surrounded by piles of 1,789 human bones.

Experts say the Aztecs usually cremated the remains of high-ranking members of their society, and even among buried commoners they haven't found such a large aggregation of bones.

The National Institute of Anthropology and History says some of the human bones show what may be cut marks.

Archaeologist Susan Gillespie said Tuesday that the find is unprecedented for the Aztec culture.

Researchers say they also found the buried trunk of what may have been one of the sacred trees that the Azetcs believed held up the firmament.