Mexico City's mayor on Monday said no expense will be spared and no line of investigation discarded in finding the killers of four women and a photojournalist, who had fled the state where he worked fearing for his safety.
The United National High Commission on Human Rights also condemned the killings, saying the bodies had signs of torture and sexual violence and that the climate of impunity "is one of the obstacles to practicing freedom of expression in Mexico."
"We are all outraged by this crime," Mayor Miguel Angel Mancera said in a news conference. "There will be no impunity in this matter. No line of investigation will be discarded."
Journalist protection groups have expressed fears that authorities won't consider the killing of Ruben Espinosa as being related to his work, even though colleagues say he fled the state he covered fearing for his safety.
Prosecutor Rodolfo Rios Garza said Sunday that authorities were following protocols for crimes against journalists and crimes against women, as well as looking at robbery as a possible motive in the case.
But when dealing with slayings of journalists, authorities in Mexico historically have been quick to discard their work as a motive, though the country is the most dangerous in Latin America for reporters. Some 90 percent of journalist murders in Mexico since 1992 have gone unpunished, according to the Committee to Protect Journalists.
"What's particularly pernicious is that violence against the press is violence against society," said Dario Ramirez, director of the Article 19 free press advocacy group. "There are many places in the country where silence paves the road so that organized crime, corruption, everything that destroys a society can continue in a manner without ... setbacks or obstacles."
Espinosa was being buried Monday following a private memorial service.
The city prosecutor's office said it was waiting on tests to confirm reports that the victims were tortured and some of the women may have been sexually assaulted.
An official from the prosecutor's office said three of the female victims have been identified, but a fourth, presumed to be Colombian, has not.
Rios gave their ages as 18, 29, 32 and 40. All were shot in the head with a 9 mm weapon. Espinosa sustained severe injuries to his face before he was killed, Ramirez said.
Rios also said the apartment was ransacked and robbed. Three of the women lived there and a fourth was the housekeeper. One woman was a friend of Espinosa's from Veracruz state, where he had worked for eight years.
The bodies were found late Friday in a middle-class Mexico City neighborhood. The building was in range of several security cameras on the street and Rios said officials have video evidence in the crime. The attackers would have had to go through two doors to get inside, and neither had signs of damage or break-in.
Friends said Espinosa had fled Xalapa, the capital of the Gulf Coast state for Mexico City in June after saying that unknown people were following him, taking his photograph and harassing him outside his home. Veracruz has been a dangerous state for reporters, with 11 journalists killed since Gov. Javier Duarte took office in 2010. Two more, including Espinosa, have been killed outside of the state and three have gone missing.
Fears that Espinosa's death could end unpunished were fueled by Sunday's news conference, when Rios never acknowledged that Espinosa was seeking refuge in Mexico's capital, saying he came to the city for "professional opportunities." The comment led to shouts and protests from reporters.
Espinosa had been working for the investigative newsmagazine Proceso and other media outlets
Duarte issued a statement Sunday saying he lamented the "aberrant" killings in Mexico City and was confident that prosecutors will solve the case as soon as possible.
In June, he had accused some reporters of being involved in organized crime.
"We all know who is involved in the underworld," Duarte said. "There's no reason to confuse freedom of expression with representing the expression of criminals via the media."
Article 19 said Espinosa's death is a milestone in violence against the press because he was the first journalist to be killed in exile in the capital. The agency said in the last five years it has helped about 70 journalists under threat find refuge in the capital.