A journalist and author known for his coverage of Mexico's drug war was killed Monday in the western city of Culiacan, in Sinaloa.

Javier Valdez, 50, was fatally shot while walking near the offices of Riodoce, a newsweekly he helped found. Investigators will look into the possibility that Valdez's killing was connected to his work as a reporter.

"Another journalist killed. I am going to re-read Malayerba tonight. If you haven't read it, I suggest you to do it. So he (Javier Valdez) can keep talking. He was an extraordinary man and journalist," posted Mexican author Emiliano Monge on Facebook. 

Mexico is one of the most dangerous countries in the world for journalists to work.

A total of 126 journalists have been killed in Mexico since 2000.

Recognized as an expert on the impact of the drug trade on Mexican society, Valdez was honored in 2011 by the US-based Committee to Protect Journalists with the International Press Freedom Award. 

Later that year, Valdez and his colleagues at Riodoce received a Maria Moors Cabot Prize from the Columbia University School of Journalism.

Besides his role with Riodoce, Valdez was the Sinaloa correspondent for national daily La Jornada and the author of several books, including "Miss Narco," based on the story of the 2008 winner of Our Sinaloa Beauty, Laura Elena Zuñiga.

The beauty queen was arrested along with her boyfriend and six other men on firearms and money laundering charges on Dec. 23, 2008.

Though Zuñiga was released a few weeks later due to lack of evidence, her story inspired Mexican director Gerardo Naranjo's 2011 film "Miss Bala."

In an interview with EFE last October marking the publication of his book "Narcoperiodismo," Valdez said that "valiant" and worthwhile journalism was becoming ever rarer in Mexico as organized crime and corrupt officials moved to silence independent voices with bullets or bribes.

Last weekend, seven journalists were briefly detained and threatened by a large group of armed men in the southern state of Guerrero.

On April 29, Filiberto Alvarez Landeros was murdered in Tlaquiltenango, a city in the central state of Morelos, as he was heading home after wrapping up his radio show.

In March, Cecilio Pineda was murdered in the southern state of Guerrero; Ricardo Monlui was killed in the northwestern state of Sinaloa; Miroslava Breach was killed in the northern state of Chihuahua; and Maximo Rodriguez was killed in the northwestern state of Baja California Sur.

Eleven journalists were murdered and 426 attacks on the media were registered in Mexico in 2016, the press rights group Article 19 said in a report released earlier this year.