The bodies of 11 men were found in eight clandestine graves in a forested area in Michoacan, a state in western Mexico, officials said.
The bodies were found on Wednesday night in a field used to gather resin from trees in La Venta, a village located outside the city of Hidalgo, the Michoacan Attorney General's Office said.
The field is one kilometer (0.62 miles) from the federal highway that links Morelia, the capital of Michoacan, to Mexico state, which surrounds the Federal District and forms part of the Mexico City metropolitan area.
Investigators found evidence that suspected members of the Caballeros Templarios drug cartel operated at the site, the AG's office said.
Crime scene investigators and state police continue digging in the field, searching for more human remains, the AG's office said.
A total of 29 suspects, including a man who claims to have murdered five of the victims, have been arrested in connection with the clandestine graves, the AG's office said.
Police officers from Hidalgo state, officers from the city of Zitacuaro and paramedics are among the suspects, prosecutors said.
Investigators are looking at the possibility that the killings were committed by the Caballeros Templarios cartel, which has been fighting the rival Familia Michoacana, a gang that mainly operates in Mexico state, for control of the illegal drug trade in the area.
Federal security forces killed the Caballeros Templarios cartel's two top leaders, Nazario Moreno Gonzalez and Enrique Plancarte Solis, in February and March, respectively.
Moreno and other members of the Familia Michoacana gang formed the Caballeros Templarios organization after he was reported killed by the government in 2010.
The Caballeros Templarios cartel, which deals in both synthetic and natural drugs, commits murders, stages kidnappings and runs extortion rackets that target business owners and transport companies in Michoacan.
The cartel uses Michoacan's 270 kilometers (168 miles) of coastline to smuggle chemical drug precursors for the production of synthetic drugs into Mexico. EFE