They have put up a menacing fight on the streets, threatening everyone from journalists to police. Now Mexican drug cartels are waging a war on a new battlefield, this time against social media users.
They are targeting Twitter and Facebook users, and in the past two months, four people have been murdered after posting about drug cartels online.
Experts say the cartels are keen to the power of the Internet as a wide reaching tool, so in exchange they have launched a violent and threatening campaign. The latest social media murder was just last week after a journalist posted a tweet about drug cartels.
Lynne Walker works with the Institute of the Americas at UCSD. She says the murders have sent a chilling effect to journalists, causing many to stop from even reporting on drug cartels.
In the end she says it denies information that the public needs about what's going on in the country.
While the drug cartel violence may be hundreds of miles away, for many, the effects are wide reaching.
“Who knows who this really affects. What we know is that four journalists in Nuevo Laredo and a border city have been killed and their killings have been blamed on what they've put out on social media…but we don't know how far this goes,” says Walker.
A group of journalists in border towns along the Texas-Mexico border have issued what they are calling a "Twitter manifesto."
It outlines the threats against them by the cartel, stating that they have the right to post online and that the government should guarantee their online security.