A police officer and four civilians have been killed by gunmen armed with assault rifles in the northern Mexican industrial city of Monterrey, the Nuevo Leon State Investigations Agency (AEI) says.
Gunmen staged two attacks in Santa Lucia, a neighbourhood in the northern section of the city, where at least 17 drug-related shootings have occurred in the past few weeks.
Three men standing outside a house were gunned down with assault rifles, the AEI said, adding that the victims were in the used car business.
Another civilian and a police officer were shot dead a few minutes later.
The police officer died while being treated at a hospital, the AEI said.
About a dozen multiple murders have occurred in the past year in Santa Lucia, with officials blaming the violence on the war between the Gulf cartel and Los Zetas for control of Monterrey.
Mexico's drug war death toll stood at 47,515 from December 2006 to September 30.
The murder total has grown every year of President Felipe Calderon's military offensive against the well-funded, heavily armed drug cartels.
Unofficial tallies published in December by independent daily La Jornada put the death toll from Mexico's drug war at more than 50,000.
Ejecutan a otros 5 en Valles de Santa Lucía