Turf wars among imprisoned drug gang leaders are responsible for a wave of violence in northern Mexico, the country's new attorney general Daniel Cabeza de Vaca said May 27. Ironically, Mexico's success in putting drug lords behind bars has prompted a bloody scramble for control of the international trade, with some leaders issuing commands from their prison cells. "Some of the leaders of the big, known cartels are operating behind bars, and that in large part creates the climate of conflict," he said.

The latest wave of killings has rocked Sinaloa state on Mexico's north Pacific coast, home to the cartel of drug baron Joaquin "El Chapo" Guzman, who escaped from prison in 2001. "They are struggling to control cities like Culiacan using executions," Cabeza told reporters, referring to Sinaloa's capital. "We have the cartels that we all know. But these are breaking apart, forming subgroups."

About 500 people have died in gang shootings across Mexico this year - many slain execution-style, with their hands tied behind their backs. Nine were killed in Sinaloa alone in the last week of May. A federal agent died May 26 in a shootout with two men believed to be members of the Zetas, soldiers turned cartel enforcers in Matamoros. The Zetas are believed to work for jailed Gulf Cartel kingpin Osiel Cardenas.

Cabeza, formerly a legal advisor to President Vicente Fox, took over as attorney general this month, replacing Rafael Macedo de la Concha, who was forced out over charges against Mexico City's populist mayor. (See our last post.) With little experience in law enforcement, Cabeza is seen by some as a weak figure, and the transition has occurred just as the violence has escalated. Macedo was applauded by Washington for being tough on drugs and was responsible for jailing drug bosses such as Cardenas and Tijuana Cartel jefe Benjamin Arellano Felix. (LAT, May 28)

The violence also comes just as plans are proceeding for increased border security and miltiary cooperation among the three NAFTA partners.