At least 15 people were killed at a nightclub here on Saturday.
Citing local media, Al Jazeera reported that seven people were also injured in the early hours of Saturday when a group of armed men pulled up in three vans at the La Playa Men's Club in the city of Salamanca and opened fire.
According to Al Jazeera, the authorities in the state of Guanajuato have launched an operation against criminal gangs involved.
It is pertinent to note that Salamanca, which is a site of the main pipeline of the state oil company Petroleos Mexicanos (PEMEX) is where fuel thieves have cost the firm around 3bn USD in recent years.