Thirteen suspects died in a battle between gunmen and Mexican security forces, the attorney general of the central state of Zacatecas said.
"In fact, there were 13 killed by the army in the community of Bañuelos, Sombrerete (municipality), Arturo Nahle said on Twitter.
The shooting broke out around 2:00 p.m. Thursday after Federal Police on patrol spotted a group of armed men and followed in pursuit, newspaper Imagen de Zacatecas said in its online edition.
Nahle later told Milenio Television that elements of the army's 97th Battalion confronted a "heavily armed" group affiliated with a criminal organization operating in Sombrerete and the nearby towns of Fresnillo and Rio Grande.
Residents had reported sightings of armed men traveling in crew-cab pickup trucks and armor-plated vehicles, prompting the Federal Police and the military to mount frequent patrols in the area, the Zacatecas attorney general said.
A suspect who survived the shootout identified himself as a member of the Gulf drug cartel, Nahle said.
"This is a group that has ravaged the region with kidnappings, robberies, extortion," he said, adding that federal authorities will take charge of the investigation because it concerns organized crime. EFE