Researcher Alejandra Jasso Pena says they also found ceramic flutes, bowls, incense burners, the remains of a dog that was sacrificed to accompany a child in the afterlife and other artifacts of a pre-Columbian civilization.
Jasso Pena said Friday that construction was about to start on five buildings in a Mexico City neighborhood when the National Institute of Anthropology and History asked to carry out an excavation of the site first.
Experts suspected the site was an important ceremonial center for the Tepanec tribe between 1200 and 1300. The influential traders living there were called Pochtecas.
Archaeologists say excavation is continuing at the site.