At least 30 journalists are thought to have either been killed or gone missing in Mexico since President Felipe Calderon took office nearly 4 years ago. <br /><br />Journalists covering the Mexico drug war say their lives are in danger as traffickers threaten to violently silence them. <br /><br />This Thursday, a 21 years-old photographer have beenkilled and another severely injured in the northern city of Ciudad Juarez. <br /><br />Local authorities say that while the incidents could have been a case of mistaken identities, it is also possible that photographers were directly targeted by the drug cartels. <br /><br />Al Jazeera's Mariana Sanchez reports from Mexico city.