Mexican authorities are searching for gunmen who killed at least 12 people and injured three more after opening fire in a bar in central Mexico on Saturday evening.

Gunshots were reported at the bar in the city of Irapuato in the central state of Guanajuato at close to 8 p.m. local time Saturday, the city’s Secretary of Citizen Safety said in a statement.

Paramedics confirmed the deaths of six men and six women after arriving on scene, according to the statement. It is unclear who the victims are and how many gunmen were involved in the shooting.

A search operation for the attackers is underway with support from Guanajuato’s Secretary for Public Safety as well as the state’s prosecutor general’s office, the Secretary of National Defense, and the National Guard.

This is the second mass shooting in less than a month in the state of Guanajuato, which has been convulsed in recent years by brutal turf wars between rival drug gangs, according to Reuters.

The state is a major manufacturing hub and production site for many of the world’s top carmakers. 

It is attractive to drug cartels for the same reason it is to auto manufacturers: road and rail networks that lead straight to the US border.

President Andres Manuel Lopez Obrador has struggled to deal with gang violence since taking office in late 2018, according to Reuters.

Although the number of homicides has fallen slightly this year, Lopez Obrador’s term is set to be the bloodiest in recent history.