JOIN USThe state's interior secretary, Morelos Jaime Canseco Gomez, told EFE Thursday that all of the victims are believed to be Mexican men.
He said the two new mass graves were found just outside the town of San Fernando, one with nine bodies and the other with four. They were discovered about 30 km from the rural community of La Joya, where eight other graves with 59 bodies were located earlier this week.
Investigators determined that these newly discovered victims were killed recently and therefore will be included in the ongoing probe into the other slayings, Canseco said.
Asked about the nationality of the first 59 bodies, which still have not been fully identified, the state interior secretary ruled out the possibility that they were undocumented immigrants.
"We're deducing that from the people's anthropomorphic features and the absence of tattoos, which are frequent in persons from other regions" of Latin America, he said.
A mass grave containing the bodies of 72 mostly Central American undocumented migrants was discovered last Aug 24 at a ranch outside San Fernando.
Los Zetas, considered Mexico's most violent drug cartel, is suspected of murdering the migrants after they refused to work for the drug mob.
Questioned as to whether some organised crime gang may be behind these latest killings, Canseco said that would be determined by the federal Attorney General's Office, which is supporting the investigation and is holding 14 suspects.