One man has been arrested in connection with the July 31 murder of Mexican photojournalist Rubén Espinosa, social activist Nadia Vera, their two roommates and their housekeeper. They were all beaten, tortured and shot in the head in their apartment in Mexico City. Two other suspects are still yet to be found.

Espinosa’s death adds one more to the dozens of journalists killed in Mexico over the last few years. Depending on who is doing the counting, between 88 and 127 journalists have been killed in Mexico since 2000.

Espinosa worked for the magazines Proceso, Agencia Cuartoscuro and AVC Noticias in the Mexican state of Veracruz, though his murder occurred outside the state. The state’s governor, Javier Duarte, has so far seen 14 journalists killed in Veracruz during his tenure. According to press freedom groups, Veracruz is one of the most dangerous states for journalists in Mexico and about 90 percent of journalist murders in Mexico go unpunished.

Journalists from outside the state have also recently been murdered or reported missing. Meanwhile, Vera — a member of the student movement #YoSoy132, who was killed alongside Espinosa — had told local television stations that if she was killed, it would be Duarte’s fault.

On August 2, Duarte gave a statement declaring that he “lamented” the murders and that he supported a full investigation into the deaths. However, on June 30 — in a meeting with reporters in Poza Rica, Mexico,— Duarte seemed to threaten any journalists involved in reporting on criminal activity.

“We all know which of you have links or are mixed up with criminals. I ask you to behave yourselves,” Duarte told reporters. “We will shake the tree, and many rotten apples will fall.”

This slew of missing and murdered journalists has spurred protests and huge rallies around Mexico, Spain, the United States and the rest of the world about the threat to freedom of the press posed by these killings. They have also drawn the attention of human rights organizations and press freedom groups like ARTICLE 19 and the Committee to Protect to Journalists, or CPJ.

“The violence of which Espinosa was victim is publicly known of by the authorities charged with protecting journalists in Mexico,” said Darío Ramírez, ARTICLE 19’s Director for Mexico. “This homicide puts the situation in Veracruz, and the negligence of local authorities in providing protection, sharply into focus.”

Espinosa was well-known for his work on protests and resistance movements, including protests against media repression and the 2012 murder of Regina Martínez, another journalist killed in Veracruz. At one of these protests, state officials reportedly told Espinosa to “stop taking photos” if he didn’t “want to end up like Regina.” In February 2014, Espinosa shot the cover photo for Proceso magazine, which included Duarte accompanied by the headline “Veracruz, lawless state.”

In June, after photographing students being beaten by masked men during election protests, Espinosa moved to Mexico City, a common place for journalists to seek refuge. He claimed that he was being followed by armed men with cameras, but thought he’d be safe upon leaving Veracruz.

“I had to leave due to intimidation, not because of a direct threat, per se, but out of common sense,” Espinosa told news outlet Rompeviento in his last interview. “There had just been an attack on students, who were brutally beaten with machetes and everything, and so we cannot, in this situation, do less, with any kind of threat or intimidation, because we do not know what will happen. In Veracruz, there is no rule of law.”

Shortly after the move, though, Espinosa was murdered in what many thought was a safe place for threatened reporters to go.

“Rubén’s murder is a clear message to all journalists: There is nowhere safe to go in Mexico — impunity reigns,” Felix Márquez, a fellow journalist and close friend of Espinosa, told The Guardian. “Journalists in Veracruz reporting the truth are being slaughtered. Eighty percent of journalists in the state have been co-opted; the remaining 20 percent of us are at risk for doing our jobs.”

Despite claims that the murder had nothing to do with Espinosa’s work as a reporter, many journalists and activists insist that their colleagues were murdered precisely for their journalism and activism. They are now protesting in various cities and demanding that an independent investigation be done into these killings.

“We don’t know what will happen next,” Laura Carlsen of the Center for International Policy told Democracy Now. “There’s a lot of fear that the government will try to sweep this under the rug. But there will be a constant pressure from civil society to make sure that these political factors are given primary importance in the investigation and that the investigation goes as high up as it needs to go in terms of responsibilities.”

Despite their colleagues’ unfortunate death, many Mexican journalists insist that the threat of being killed will not stop them from reporting the facts.

“I am scared, we are all scared, but I won’t put down my camera,” Márquez told The Guardian after Espinosa’s funeral. “Rubén’s death has made sure of that.”