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Mexico now ranks alongside Iraq as the deadliest country in the world for journalists in 2017. It has even surpassed war-torn Syria, according to the Committee to Protect Journalists.

At least four journalists have been killed in Mexico this year. CPJ has directly linked all of those to murders to the reporters' work, while the motive behind another death is still being investigated.

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"Every journalist in Mexico is a target," said freelance journalist Luis Chaparro who works in Juarez, a city the Mexican state of Chihuahua.

"I, as many of my colleagues, feel very, very unprotected," Chaparro said.

Several factors have brought cartel violence roaring back in Chihuahua and other parts of Mexico -- from fragmented cartels fighting for turf and influence over government officials to rising opioid use in the United States.

"They just killed my colleague Miroslava recently," said Chaparro. "I felt like that f------g bullet was too close for me."

Miroslava Breach, who reported on drug cartels and corruption, was shot eight times in March as she drove away from her Chihuahua home. Police have identified two suspects in her murder, but no one has been arrested.

It's estimated 90 percent of murders of journalists in Mexico are unsolved or not thoroughly prosecuted.

"Perpetrators are not arrested and not punished," said Carlos Lauria, CPJ's Program Director for the Americas, "and they do it because they feel like there is no consequence."

The CPJ estimates that more than 40 journalists have been killed for their work in Mexico since 1992. In 50 other murders, a motive has still not been confirmed.

Mexico's federal government has implemented a program to protect journalists who have been threatened, but Lauria said it's clearly not working.

The killings, he said, are a threat to Mexican democracy. "It's affecting the fundamental human rights of all Mexicans for freedom of expression and access to information," Lauria said.