Mexican agents arrested a former medical student who seized control of the remnants of the Juarez cartel, the country's attorney general said Monday, shedding light on a split within what was once Mexico's most powerful cocaine smuggling gang.

Ricardo Garcia Urquiza, captured in a shopping mall in Mexico City on Nov. 11, is accused of overseeing an organization that moved up to 5 tons of Colombian cocaine a month into Mexico and on to the United States.

Attorney General Daniel Cabeza de Vaca said that since late 2004, Garcia Urquiza was responsible for as much as 20 percent of the narcotics that reached America's streets from Mexico.

"This was a mega-cartel, perhaps not as violent, perhaps operating in a different manner, but a mega-cartel," he said.

Garcia Urquiza, his brother Jesus Omar, and Maria Nereida Garcia, a suspected cartel accountant who was arrested leaving her home with nearly $3 million in cash, were among 11 people captured as part of an investigation dubbed "New Generation."

Cabeza de Vaca said the name reflects the fact that the suspects fall into a modern category of drug lords who live in relatively modest homes and drive ordinary vehicles without small armies of attention-attracting body guards.

"They act more like businessmen," Cabeza de Vaca said.

The Juarez Cartel was considered the country's largest drug trafficking organization under the leadership of Amado Carrillo Fuentes.

After Amado's death from botched plastic surgery in July 1997, control of the cartel fell to his brother, Vicente.

The split between Vicente Carrillo Fuentes and a rival faction controlled by Joaquin "El Chapo" Guzman and other drug lords — known as the Sinaloa cartel — came to a head in 2004, when Vicente's brother, Rodolfo Carrillo, was killed at the orders of Guzman, Defense Secretary Gen. Gerardo Clemente Vega said.

Fearing for his life, Vicente Carrillo Fuentes fled, but continues to operate with a few cells of drug smugglers, Vega said.

In his absence, control of the gang allegedly fell to Garcia Urquiza.

The faction of the Juarez cartel controlled by Garcia Urquiza had no link with the Sinaloa cartel, but the two gangs have also not engaged in the kind of bloody war for territory that ensnared other smugglers, Cabeza de Vaca said.

Guzman, who escaped from a western Mexican prison in 2001 and has overseen a bloody war for control of the U.S.-Mexico border city of Nuevo Laredo, is often referred to as the country's top drug lord. Garcia Urquiza's arrest brings authorities no closer to catching Guzman, Cabeza de Vaca said.

A spokesman for the Drug Enforcement Administration in Washington had no comment on the case.