State authorities say that a commando of gunmen burst into a bar in the city of Torreon in northern Mexico and killed seven people before fleeing in waiting vehicles.
The state Attorney General's Office in Coahuila said the gunmen entered the Tornado bar quickly early Sunday morning and shot the victims from close range. Five others, including a woman, were injured in the attack.
Police were investigating the attack but so far no arrests have been made. Coahuila state is across the border from Texas.
Authorities say the Zetas and the Sinaloa drug cartels are fighting each other over control of smuggling routes in Coahuila where Torreon is located. Last week, six people were killed inside different establishments in the city.