Gunmen kill 11 at football field in Mexico’s Guanajuato state

Six people are still receiving medical attention for injuries

A group of armed attackers killed 11 people at a football field after a match in the Mexican city of Salamanca, the latest outburst of violence in Mexico's Guanajuato state, officials said late on Sunday.

Six people were still receiving medical attention for injuries, Guanajuato's state attorney general's office said in a statement on Sunday evening. The office promised a thorough investigation.

A motive for the attack was not immediately clear, Salamanca Mayor Cesar Prieto said in a video statement shared on Facebook.

A woman and a child were among a total of 12 injured in the "regrettable and cowardly" attack in the Loma de Flores community during a social gathering, Prieto said, describing the incident as a severe social breakdown.

Guanajuato has been for many years one of the most violent regions in the country, driven by violent turf wars between rival cartels. Just on Saturday, five people were "assassinated" in two separate attacks near Salamanca, Prieto said.

Salamanca is also home to one of the seven refineries operated in Mexico by state oil company Pemex. Widespread fuel theft is one of Mexico's largest criminal economies.

"This incident adds to a wave of violence that we are sadly experiencing in the state, and particularly in Salamanca," he added. "Unfortunately, criminal groups are trying to subjugate the authorities, which they will not achieve."

Guanajuato borders Jalisco, whose capital Guadalajara is one of the host cities for this year's soccer World Cup.

Guanajuato Governor Libia Dennise in a statement on social media called the attack "unacceptable" and said security in the state had been reinforced, without providing details. Asked at her regular press conference for information about the attack on Monday morning, President Claudia Sheinbaum deferred to the state attorney general's office.

The state attorney general's office said it is coordinating efforts with municipal, state and federal authorities to strengthen security in the area, protect its people and find the likely perpetrators.

"Those responsible will be found," Prieto added in his Facebook remarks.