Gunmen stormed two strip clubs in northern Mexico over the weekend, killing three people and wounding five others in the latest spate of violence in Nuevo Leon state, officials said Monday.
Men armed with assault rifles entered the Blue Tequila bar in the city of Monterrey late Sunday, killing two clients with shots in the neck and beating another person, said a state government spokesman, Jorge Domene.
A few hours earlier, three gunmen also toting assault rifles had killed a client and wounded another at the New Jungle strip club in the town of Cadereyta, some 30 kilometers (19 miles) from Monterrey.
They chased the barman, who fled to a nearby bar, where the gunmen wounded three other people.
"In both cases armed men entered the establishments and opened fired," Domene said.
Authorities are investigating whether the shootings are linked to a battle between the Zetas and Gulf drug cartels for control over such establishments, according to sources in the state investigations agency.
The attacks came one week after eight people were killed in a shooting at another strip club in Monterrey, Mexico's industrial center and third biggest city.
The Monterrey metropolitan area has been the scene of a bloody conflict between the Gulf cartel and the Zetas, two criminal organizations battling over control of the region.
The number of homicides in Nuevo Leon surged surged to 2,177 in 2011 from 951 a year earlier, according to official statistics released Monday.
More than 50,000 people have been killed in drug-related violence across Mexico since 2006, when the military was ordered to take the lead in a crackdown against the country's powerful drug cartels.