A policeman cordons off a crime scene where gunmen tried to kidnap a government official outside the Topo Chico prison, in a gruesome war between Mexico's powerful Gulf cartel and its former armed wing, the Zetas
A policeman cordons off a crime scene where gunmen tried to kidnap a government official outside the Topo Chico prison, in a gruesome war between Mexico's powerful Gulf cartel and its former armed wing, the Zetas, in Monterrey, in this June 11, 2010 file photo. REUTERS

In Mexico, a missing female journalist was found decapitated in Nuevo Laredo, a city near the Texas border. Marisol Marcia Castaneda, an editor with Nuevo Laredo newspaper Primera Hora, was though to have been murdered by a powerful drug cartel in retaliation for posts she made on a social media network, according to authorities.

Castaneda is the tenth journalist killed in Mexico this year and the 74th since 2000, according to Mexico's Human Rights Commission. Her death is also the third Internet-related killing in Neuvo Laredo in September alone.

Earlier this month, police discovered the bodies of a man and a woman hanging from a pedestrian bridge in the city. The two were thought to have been tortured and then killed for tweets they made on Twitter about the local drug trade.

The two murders were the first time that bloggers were seriously targeted by drug cartels, and could be the start of a deadly new trend. Blogs that report on Mexico's drug war have been threatened in the past, but until this month none have been seriously attacked.

Traditional media outlets are as frightened of drug gang retaliations as many citizens, and newspapers often censure their own reports to downplay cartel crimes. This places the reporting burden on bloggers, and now, Twitter users, and it is no surprise that Castaneda posted her comments on the Nuevo Laredo Live Web site and not in Primera Hora.

Sadly, Castaneda's murder will be tallied along-side the rest of the victims of Mexico's drug war. People are killed nearly everyday in Mexico, and decapitations are neither unusual nor extreme. More than 41,000 people have been killed since President Felipe Calderon began his counter-offensive against drug cartels in 2006, which more than are killed in some wars.

A note left on Castaneda's body implicates powerful drug cartel Los Zetas, who are also thought to be responsible for the murders of the two Twitter users. Los Zeta's territory runs up Mexico's east coast, and the group, founded by former special forces soldiers, is one of Mexico's most notorious cartels.

Nuevo Laredo en Vivo and social networking sites, I'm The Laredo Girl, and I'm here because of my reports, and yours, the message on Castaneda read. For those who don't want to believe, this happened to me because of my actions, for believing in the army and the navy. Thank you for your attention, respectfully, Laredo Girl...ZZZZ.

The two bodies hanging from the bridge also had a note attached that was signed simply Z.

Despite the government's push into illegal drug trafficking, which has led to a number of significant and high-profile arrests, violence in Mexico appears far from abating.

Last week, two pick-up trucks drove onto a rush hour highway and dumped 35 dead bodies in the street in Veracruz, which is about 14 hours away from Nuevo Laredo, but still part of the Zetas' territory.

Seemingly no one is outside the many drug cartels' grasp. Last Saturday, the body of Mexican congressman Moises Villanueva de la Cruz was found murdered, lying on a highway in the coastal state of Guerrero.

Since 2010, a total of 19 mayors have been murdered, most recently Zucuaplan Mayor Jose Eduviges Nava Altamirano. The town of Zucuaplan is also in Guerrero. Additionally, more than 50 police officers have been killed in Mexico since October 2010.

President Calderon insists that his crackdown is not responsible for the violence, claiming instead that cartel expansion, as well as the United States' insatiable appetite for illegal narcotics, is to blame. Retaliation has nothing to do with it, he says.

The armed forces are not part of the problem, but part of the solution, Calderon said earlier this month. If we hadn't done anything, instead of the utopian country some think we would live in, we'd be overtaken by the cartels.