Javier Valdez was shot and killed when assailants opened fire on his vehicle in the state capital Culiacan, according to RioDoce, the local media outlet he co-founded and where he continued to work. The official was not authorised to discuss the matter publicly and spoke on condition of anonymity, the Associated Press news agency reported.
Riodoce confirmed the news of Valdez's killing on its website.
Valdez worked for the national daily newspaper La Jornada and the local weekly Riodoce.
In 2011, the CPJ gave Valdez an International Press Freedom Award for his coverage of the victims of the drug war.
Cardenas reported extensively on drug trafficking, and is the fifth journalist to be killed in Mexico this year.
Last weekend a group of reporters said a large group including children bearing semi-automatic weapons took their equipment while they covered unrest in the state of Guerrero.
President Enrique Pena Nieto said on Twitter that he had ordered an "investigation of this outrageous crime".
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Valdez was a nationally and internationally-recognised journalist who authored several books on the drug trade, including "Narcoperiodismo" and "Los Morros del Narco". The former is a look at the relationship between journalism and organized crime, and the latter chronicles the lives of young people swept up in Mexico's criminal underworld. "I don't want to be asked, 'What were you doing in the face of so much death. why didn't you say what was going on?'"
Mexican and foreign journalists paid homage to Valdez on social media, describing him as a courageous writer and generous friend whose killers must be brought to justice to deter future slayings.
Mexico is one of the most risky places to be a journalist, with the vast majority of attacks on the media unpunished.
He was considered a rare source of independent, investigative journalism in Sinaloa, said Jan-Albert Hootson, the Mexico representative for the New York-based Committee to Protect Journalists.
"Sinaloa, Valdez's home state is infamous in Mexico's drug world", Carrie says.
At the time, the CPJ said 38 journalists have been killed in Mexico since 1992.
Last Wednesday, the federal Attorney General's Office replaced the head of its division responsible for investigating journalist killings.
In a 2017 report titled "No Excuse", journalist Adela Navarro Bello wrote for the CPJ that "covering corruption in Mexico means living with impunity".