The demise of Mexico's enigmatic pre-Hispanic city of Teotihuacan stemmed from a conflict among the civilisation's elite classes, with buildings set ablaze in the clash, according to a study.

The famed pyramids of the Sun and Moon are among the majestic structures that remain at the tourist site near Mexico City, centuries after Teotihuacan's population vanished.

The Pyramid of the Sun is one of the few remnants of the mighty fallen Teotihuacan civilisation. Credit:Reuters

What caused the civilisation to abandon the sprawling city in the 7th century has been the subject of many studies, with political, economic and social problems believed to be behind the exodus.

Linda Manzanilla, an anthropologist at the National Autonomous University of Mexico, now says the collapse was the result of a confrontation between the city's rulers and an "intermediate elite" comprised of entrepreneurs.