Iran Villarreal Belmont, who had also contested for a municipal council seat in San Luis de la Paz, was reportedly kidnapped by armed men on Thursday before his body was discovered the following morning.
Authorities in Guanajuato confirmed that Villarreal had been shot and killed.
The state prosecutor's office has classified the murder under crimes related to freedom of expression.
His work as a journalist and his outspoken criticism of local government officials, including Mayor Ruben Urias of the National Action Party, are being considered in the investigation.
Villarreal managed a Facebook news page called Observatorio Ciudadano (Citizen Observatory), which had around 8,400 followers.
Through this platform, he covered events and issues affecting his city, often questioning local authorities and governance.
His political affiliation with the Movimiento Ciudadano party and his past attempt to secure a municipal seat had made him a well-known figure in the region.
Following his killing, Movimiento Ciudadano issued a statement demanding that authorities prioritize his journalism work as a key line of investigation.
Press freedom groups and human rights activists have also raised concerns over the increasing threats faced by journalists in Mexico.
Guanajuato, a state known for its industrial development and tourist attractions, has also become one of the most violent regions in Mexico.
Official statistics rank it as the deadliest state, with numerous homicides linked to criminal gang rivalries.
The ongoing conflict between the Santa Rosa de Lima cartel and the powerful Jalisco New Generation cartel has fueled violence in the area.
The murder of Villarreal is part of a larger pattern of attacks against journalists in Mexico.
Over the years, many reporters have been threatened, abducted, or killed while covering issues related to crime and corruption.
Since 2006, when the government deployed the army to fight drug cartels, more than 480,000 people have been killed in drug-related violence across the country.
Villarreal’s death has sparked outrage, with many calling for justice and better protection for journalists.
His case adds to the growing list of media workers targeted for exposing corruption and crime in Mexico.
