Archaeologists have discovered what they think are ruins of an Aztec pyramid in what is now one of Mexico City's most crime-ridden districts.
Construction workers unearthed ancient walls in the busy Iztapalapa neighbourhood in June, and government archaeologists said on Wednesday they believe they may be part of the main pyramid of the Aztec city, destroyed by Spanish conquistador Hernan Cortes in the 16th century.
Iztapalapa, infamous for violent crime and drug dealing, has grown into a sprawling, poor district of the capital, obscuring the ruins.
Iztapalapa's ruler, Cuitlahuac, nearly annihilated Cortes and his Spanish troops in 1520 in what became known as the Sad Night. After eventual victory, Cortes destroyed the city.
Mexico City is littered with pre-Hispanic ruins. In October, archaeologists in the city's central Zocalo square unearthed a 15th-century Aztec altar and a 12-ton stone idol just yards from downtown traffic.
The Aztecs, a warlike and deeply religious people who built monumental works, ruled an empire stretching from the Gulf of Mexico to the Pacific Ocean and encompassing much of modern-day central Mexico.