The incident took place during a town hall meeting in the village of San Miguel Totolapan, which resulted in gang members opening fire on attendees.
Mayor Conrado Mendoza and his father, former Mayor Juan Mendoza Acosta, were among the victims killed, while most others are also suspected to be local officials, according to the AP.
The suspects identified themselves as the Tequileros gang in a video shared online claiming responsibility for the shooting incident, which took place as a children's fair was being held a few blocks away.
Totolopan is a mountainous town located in the Tierra Caliente region, which is known to be one of the most conflict-ridden areas of Mexico, according to the AP.
A backhoe was needed to be brought into the town's cemetary in order to scoop out enough graves to bury the many residents killed in the mass shooting.
“This act occurred in the context of a dispute between criminal gangs,” said Ricardo Mejia, Mexico's assistant secretary of public safety. “A group known as the Tequileros dominated the region for some time; it was a group that mainly smuggled and distributed opium, but also engaged in kidnapping, extortion and several killings in the region.”