In barely four years, a little-known criminal gang has grown to challenge the world's most notorious druglord, Joaquin "El Chapo" Guzman, for domination of the Mexican underworld, unleashing a new tide of violence. Once minions of Guzman's Sinaloa Cartel, traffickers of the Jalisco New Generation Cartel (CJNG) have turned on their former masters, seizing territory and buying off thousands of corrupt police.Led by former policeman Nemesio Oseguera, aka "El Mencho", the gang carved out an empire at the expense of weaker rivals.Juggling interests from China to North Africa and eastern Europe, the CJNG's advance has pushed murders to their highest levels under President Enrique Pena Nieto, who vowed to restore law and order when he took office in 2012.Pena Nieto did initially succeed in reducing violence, but a resurgence that led to 3800 murders between July and August highlights the government's failure to beat down cartels without new ones springing up in their places.Intimidating, paying off or eliminating police, CJNG leaders have ruthlessly applied lessons learned during their apprenticeship under Guzman's cartel to muscle in on rivals and snatch trafficking routes, security experts say.Bearing the brunt of the chaos are the ports, trafficking centres and border crossings that light up the multibillion- dollar trail of crystal methamphetamine from Mexico to the US, the CJNG's main source of revenue.Both savage - one gang hitman videoed blowing up victims he had strapped with dynamite - and shrewd, the CJNG is flanked by a white- collar financial arm known as "Los Cuinis". ..