A Mexican judge on Thursday sentenced one of the murderers of acclaimed journalist and AFP contributor Javier Valdez to 32 years and three months in prison for the killing, which sparked international condemnation.

The 50-year-old was a prominent chronicler of Mexico's deadly drug wars and known for writing articles critical of powerful gangs such as notorious kingpin Joaquin "El Chapo" Guzman's Sinaloa cartel.

A judge handed down the sentence against Juan Francisco Picos Berrueta for his role as co-perpetrator and organizer of the May 2017 murder in the northern state of Sinaloa, the prosecutor's office said.

Valdez's widow Griselda Triana welcomed the ruling, but noted that the alleged mastermind of the killing has yet to be prosecuted for it.

"This is an important sentence because it sets a precedent," she told AFP.

"The murder was clearly due to his work as a journalist and now everyone will know that there are heavy punishments for people who violate freedom of expression," she added.

Picos Berrueta, known as "El Quillo," was convicted last week and faced up to 50 years in prison after he refused to plead guilty in exchange for a shorter term.

Last year, one of his relatives, Heriberto Picos Barraza, was sentenced to 14 years and eight months in prison after confessing to involvement in the Valdez murder.

He had served as a driver for Picos Berrueta and another suspect, Luis Ildefonso Sanchez, who was killed before he could be arrested.

In that trial, it was revealed that the trio had links to the kingpin Guzman, who is serving life behind bars in the United States.

The prosecution alleged the assassination was ordered by Damaso Lopez Serrano, the son of a former top "El Chapo" lieutenant, who was said to have been furious at having been criticized in an article.

Mexican journalist Javier Valdez was murdered in May 2017
Mexican journalist Javier Valdez was murdered in May 2017 AFP / PEDRO PARDO

Lopez Serrano, who is imprisoned in the United States for drug trafficking, has denied involvement.

Valdez, who was shot in Culiacan, the capital of Sinaloa, was an AFP contributor for a decade, a correspondent for the daily La Jornada and a co-founder of the Riodoce weekly newspaper.

One of his final pieces was about internal struggles within the Sinaloa cartel following Guzman's capture in January 2016, before the drug lord was extradited to the US.

Thursday's sentencing came just hours after gunmen killed another journalist -- Gustavo Sanchez, in Mexico's southern state of Oaxaca. It was the second such confirmed murder this year.

The body of another journalist, Enrique Garcia, was found the same day in the central State of Mexico, although media watchdog Reporters Without Borders said it was not immediately clear if he was killed because of his work.

The group regularly ranks Mexico alongside war-torn Syria and Afghanistan as the world's most dangerous countries for news media workers.

More than 100 reporters have been murdered since 2000 in Mexico, where investigating political corruption or powerful drug cartels can have deadly repercussions.

Only a fraction of those crimes have resulted in convictions.

Valdez, who was gunned down in broad daylight outside his newspaper's offices, was a winner of the prestigious International Press Freedom Award.

The Breach-Valdez Prize for journalism and human rights is awarded in honor of him and fellow journalist Miroslava Breach, who was also murdered in 2017.

It is sponsored by AFP and the United Nations, along with several other organizations.

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