Authorities say it was from the suspected killer, former transit police officer Juan Carlos Carranza, a fugitive criminal linked to Los Zetas.
One video posted to YouTube in mid-June contained what was said to be an audio recording of a conversation between Ordaz and an unnamed crime figure, arranging to publicize criticism of alleged army abuses. Another video affirmed that Los Zetas referred to the Notiver newsroom as "Base 40."
A fellow journalist, Cesar Augusto Vazquez Chavez, published a column that accused Ordaz of acting as media coordinator for Los Zetas in Veracruz. It described a meeting between a group of police reporters and a Zetas boss, Rolando Veytia, in a restaurant. The column said Ordaz was the go-between.
Ordaz was "the one who gave them the line on what to publish and what not to publish," the column said, and offered each one a salary of the equivalent of between $665 and $1,250 a month.
"This version that circulates about Yolanda — and it is totally unprovable — that she operated like a press person for a criminal group, horrifies me," said Cerdan Diaz, the university professor. "I knew her as a student, and she didn't have any sign of criminality."
The accusations have been met with tense silence. Notiver's founder and publisher, Alfonso Salces, didn't respond to requests for comment. The columnist who made the accusations didn't answer emails seeking an interview.
Lopez's surviving elder son, who bears the same name, posted several messages on his Facebook page, calling the columnist a "drooler" and a liar. He added a lament for his profession: "Media owners are leaving us adrift. . . . We are passing through a very difficult and dark moment in journalism in our state."
Press freedom advocates acknowledge that while many Mexican journalists ply their trade with integrity, some are on the take from crime bosses.
"I've seen reporters in Sinaloa who drive Hummers on a salary of 5,000 pesos ($420) a month," said Gonzalez of Article 19.
He said gangsters sometimes pressured reporters directly, calling them on their cell phones or intercepting them on the street. In some newsrooms, powerful crime groups maintain designated envoys among the journalists to give a last-minute thumbs up or down on news reports, he added.
Journalists who ignore cartel edicts face real threats in Mexico, the deadliest place in the Western Hemisphere to work as a journalist. Mexico's National Human Rights Commission says 68 journalists were murdered in Mexico from the year 2000 to March of this year.
Colleagues who spoke only on the condition of anonymity offered up other theories of the murders, saying that Lopez and Ordaz may have been passing information to military intelligence and were killed by crime gangs in vengeance.
Cerdan Diaz, who's taught university journalism classes to hundreds of students in Veracruz over the years, said that only one conclusion was beyond a doubt.
"These executions and the decapitation of Yolanda are unequivocal signs of cruelty and malice to send a message that someone is in charge," he said.
Whoever that may be lingers murkily in the air.
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