Investigators have dug up 18 bodies in western Mexico after questioning nearly two dozen police officers who confessed to working with a drug cartel and revealed a series of mass graves.
Officials said more bodies could be found as excavation of eight graves continues. Some of the bodies were gagged and showed signs of torture, and one was a woman, said a federal prosecutors official.
The identities of the victims and any motive for the killings have not been released, but the area near the border between Jalisco and Michoacan states is the site of a turf war between the Knights Templar and the New Generation cartels.
The graves were in La Barca in a remote area by Lake Chapala, which is popular among tourists and American retirees.
The grisly discovery comes as the government scrambles to curb violence in Michoacan, where locals have formed self-defence groups to fight the pseudo-religious Knights Templar.
Mexican president Enrique Pena Nieto says homicides are down even as the state of Michoacan deals with an unprecedented level of attacks. In late October, gang members shut down electrical facilities in the state, leaving hundreds of thousands of people without power.
The discovery of the mass graves follows the capture of 22 police officers and three other men who are suspects in the disappearances of two federal investigators. The empty vehicles of the unit the two agents were travelling in were found burned earlier this month.
The official said the two agents were not among the bodies exhumed over the past six days.
He said the detained policemen confessed they turned the two investigators over to the New Generation cartel. They also told authorities they feed information to the gang.
Despite efforts to root out corruption from police departments, many officers continue to work for drug traffickers. Last week, military and federal police moved into the Michoacan port of Lazaro Cardenas, a hub for trafficking precursor chemicals used to make crystal meth, and dismissed the entire police force.
Other areas in western and southern Mexico continue to suffer from clashes between security forces and gangs or between rival cartel members.
In the state of Guerrero, authorities unearthed the bodies of five men and a woman in a lime orchard off a highway on Thursday. Although the state attorney general did not say whether a cartel was suspected in the attack, the Pacific coastal area has also suffered a wave of violence as self-defence groups have sprouted up to battle the Knights Templar.