The bodies of 11 people – nine men and two women – were found buried in a field near Ahome, a city in the northwestern Mexican state of Sinaloa.
A farmer found the bodies Tuesday in shallow graves in the community of Plan de San Luis and called police.
Coroner’s office personnel and prosecutors initially found just three bodies, but a more extensive dig turned up the other human remains.
Investigators have not identified the victims and it is not known when they were killed.
Investigators have found 116 bodies in mass graves outside San Fernando, a city in the northeastern state of Tamaulipas.
The mass graves were discovered last week in the wake of reports that gunmen had forced men off buses headed for Reynosa, located across the border from McAllen, Texas, between March 19 and March 31.
Los Zetas, considered Mexico’s most violent drug cartel, has been blamed for the wave of violence in Tamaulipas and other parts of northern Mexico.
The cartel is suspected of murdering 72 migrants last August at a ranch outside San Fernando after they refused to join the organization as hired guns.
Sinaloa is home to the drug cartel led by Joaquin “El Chapo” (Shorty) Guzman, who was arrested in Guatemala in 1993 and pulled off a Hollywood-style jailbreak when he escaped from the Puente Grande maximum-security prison in the western state of Jalisco on Jan. 19, 2001.
The Sinaloa organization, sometimes referred to by officials as the Pacific cartel, is the oldest drug cartel in Mexico and Guzman, considered extremely violent, is one of the most-wanted criminals in Mexico and the United States, where the Drug Enforcement Administration has offered a reward of $5 million for him.
Sinaloa, the birthplace of many of Mexico’s drug lords, is currently the scene of a bloody turf war between Guzman and the Beltran Leyva cartel, which arose as a splinter group of the Sinaloa organization.
A total of 15,270 people died in drug-related violence in Mexico last year, and more than 36,000 people have died since President Felipe Calderon declared war on the country’s cartels shortly after taking office in December 2006.
Calderon has deployed tens of thousands of soldiers and Federal Police officers across the country to combat drug cartels and other criminal organizations.
The anti-drug operation, however, has failed to put a dent in the violence due, according to experts, to drug cartels’ ability to buy off the police and even high-ranking officials.