Eight purported cartel gunmen were killed in this northern Mexican city in clashes with police that also left three officers and one suspect wounded, the security spokesman for Coahuila state said.

Police officers patrolling the northern part of the state capital were fired at Thursday by the gunmen, triggering a chase along several avenues, Sergio Sisbeles said.

Police received a report about armed men riding in four vehicles on two avenues in Saltillo, Sisbeles said, adding that four of the gunmen were killed in an initial clash with the security forces and two others died in a subsequent gun battle.

Three gunmen were wounded in the fighting, two of whom later died at an area hospital, while the three wounded police suffered only minor injuries, Sisbeles said.

He added that authorities had launched an investigation to identify which criminal gang was involved in the clashes.

The spokesman recalled that a wave of violence erupted at the start of the year in the southern part of Coahuila, where Saltillo is located, and later spread to the La Laguna region in the western part of the state.

Saltillo, located approximately 900 kilometers (560 miles) north of Mexico City, has been the scene of clashes in recent years pitting members of the powerful Los Zetas cartel - which controls key smuggling routes in Coahuila - against police and the armed forces.

President Felipe Calderon militarized the struggle against Mexico's drug cartels shortly after taking office in December 2006, deploying tens of thousands of soldiers and Federal Police officers across the country to combat drug cartels and other criminal organizations.

The death toll in Mexico's drug war stands at more than 50,000 since 2006. EFE