The decapitated body of a man was left Wednesday at the same monument in the border city of Nuevo Laredo where the corpse of a woman purportedly killed in retaliation for her postings on an anti-crime website had been left previously, authorities said.
A photo of the scene indicates the man was killed for reporting criminals on social media sites, raising fears drug cartels are increasingly targeting bloggers.
Police found the body at a monument on one of the city's main thoroughfares, said a Tamaulipas state investigator who spoke on condition of anonymity because he is not allowed to discuss the case.
The officer wouldn't discuss the content of the message but a photograph of the scene posted on a blog shows a handcuffed man lying on his belly on top of a bloodstained message and a chopped head nearby. The message reads "this happened to me for not understanding that I shouldn't report things on the social networks."
The message claimed the man, identified by his nickname "Rascatripas" or "Belly Scratcher," was a moderator of "Nuevo Laredo en Vivo," a website used by the city's residents to denounce crime and warn each other about drug cartel gunfights and roadblocks.
The gruesome killing may be the fourth since September in which people in Nuevo Laredo were killed by a drug cartel for what they said on the internet.
The decapitated body of Maria Elizabeth Macias, "La Nena de Laredo," or "Laredo Girl," was found at the site in September with a message that said she was killed for her reports on the website. That message was signed with the letter "Z," which refers to the violent Zetas drug cartel.
Earlier that month, the bodies of a man and a woman were found hanging from an overpass in Nuevo Laredo with a message threatening, "this is what will happen" to trouble-making Internet users and also signed with a "Z."
The Zetas have dominated Nuevo Laredo, located across the border from Laredo, Texas, for years.
"Nuevo Laredo en Vivo" has a message acknowledging Macias was a contributor and lauding her courage.
Chat messages on the website show a user with the nickname of "Rascatripas" commented Monday afternoon about the dangers of traveling on a riverside highway that connects Nuevo Laredo to Ciudad Mier.
Whether the unidentified man found Wednesday at a monument to Christopher Columbus contributed to the website it's unclear.
"We have no way of confirming whether He is the person who was killed because we're all anonymous," said a Tweet by "Nuevo Laredo en Vivo" in response to a request for comment by The Associated Press.
With local newspapers forced to avoid crime reporting by threats in many border cities Mexicans have increasingly turned to local online chat sites like "Nuevo Laredo en Vivo" to report and read about cartel activity. The site includes numbers to phone in tips to police and the military.
"We're seeing that the war in Mexico it's not only about gaining control of the streets but also controlling information," said Carlos Lauria, the Americas senior program coordinator for the New York-based Committee to Protect Journalists. "This is no longer a problem that affects just one group, for example journalists, but it affects anyone who informs ... this is putting Mexico's democracy at risk."
Users of "Nuevo Laredo en Vivo" wowed to continue reporting criminals to authorities.
"Those guys think they are so smart. They want to spread fear," wrote a user identified as Anon5218 Wednesday night. "As long as no one confirms Rasca was an honest citizen, let's leave it as a doubt and continue on."