Mexican officials are trying to calm concerns over reported US infringement of its southern neighbour's sovereignty.<br /><br />According to a New York Times report, US intelligence agents are operating in Mexico more than ever before to infiltrate drug cartels in Mexico,<br /><br />The newspaper cited security officials who said US unmanned surveillance planes and sophisticated human-intelligence gathering systems have helped Mexican authorities to kill or capture dozens of other prominent suspects involved in the drug war.<br /><br />Al Jazeera's Franc Contreras reports from Mexico City.
