At least 12 killed after masked drug cartel gunmen burst into bar and begin firing as customers cowered in terror

AT LEAST 12 people have been executed by gunmen after they barged into a central Mexico bar amid growing gang violence.

Initial reports indicate that five men and six women were killed and three others were injured in the Irapuato bar in the Mexican state of Guanajuato on Saturday around 8pm local time.

The region, now one of Mexico's most dangerous, has become the site of a blazing dispute between two rival gangs, the Santa Rosa de Lima and Jalisco New Generation cartels.

Both are knows for drug trafficking and fuel theft, among other crimes which also include murder, kidnapping and forced amputations.

Local media reported that customers had been enjoying their evening together at the Texana bar - also know as El Pantano - when the heavily armed men with their faces covered broke up and opened fire.

Customers and employees tried to flee by the bar's back door, but many did not survive. Others escaped and ran to find help as loud gunfire could be heard by scared neighbours.

In a statement, the municipal government confirmed at least 12 had died, but did not reveal the identity of the attackers or their motives.

The body of one victim was found outside the bar next to a motorcycle, while the rest of those killed were discovered inside the bar, police said.

State police, the army, the National Guard and the prosecutor's office are now hunting the criminals, the municipal government said.

This is the second mass shooting in the area in less than a month, authorities said.

In September, gunmen killed 10 people in a pool hall in the state's Tarimoro municipality.

At the time, the killers left behind two cards signed by the criminal group Cartel de Santa Rosa de Lima, who claimed responsibility for the slaughter.

In May, 11 were killed in brutal attacks at a hotel and two bars in the city of Celaya, also in Guanajuato state.

A further five were injured as suspected cartel gunmen armed with Molotov cocktails stormed the sites in a coordinated series of hits.

The nearby state of Guerrero has also been suffering from the uptake in gang violence.

Earlier this month, members of an organised crime group massacred 20 people - including the mayor inside the town hall of San Miguel Totolapan.

In total, authorities have recorded 2,115 homicides in the area between January and August.