Two reporters were gunned down, while a third was found dead in the trunk of a car. Mexico is one of the most dangerous places in the world for journalists, with a majority of the murder cases going unsolved.
Three journalists were killed this week in Mexico, local officials said on Saturday, making it the deadliest week for reporters in the country so far this year.
Jorge Celestino Ruiz Vazquez was shot dead on Friday evening in the eastern state of Veracruz.
Ruiz's colleagues at the El Grafico de Xalapa newspaper said he'd stopped putting his name on articles to keep a low profile.
His house was shot at in October and his car was also fired on, a police source told the Agence France-Presse news agency.
Veracruz state Governor Cuitlahuac Garcia said he condemned "the cowardly murder" on Twitter, adding: "We will bring those responsible to justice. His murder will not go unpunished."
Journalists brutally murdered
Edgar Alberto Nava Lopez, the founder of the online news outlet La Verdad de Zihuatanejo was also killed on Friday.
He was gunned down at a restaurant in the resort town of Zihuatanejo in the southern state of Guerrero, the local prosecutor's office said.
It was unclear whether his death was related to his work as a journalist, as Nava also worked as the city's regulations director. However, a former colleague told the Committee to Protect Journalists (CPJ) that he was threatened over his reporting.
On Tuesday, police found the body of Rogelio Barragan Perez, another journalist who worked in Guerrero state.
Barragan, who founded the online news website Guerrero Al Instante, was found in the trunk of an abandoned car in a neighboring state. His body showed signs that he was beaten on his head and neck, the CPJ said in a statement, citing local reports.