BUENOS AIRES – A powerful Colombian drug trafficker was arrested more than a month ago by the Argentine secret service and U.S. Drug Enforcement Administration agents in Buenos Aires, judicial officials said.

Luis Agustin Caicedo Velandia, accused of being the leader of one of Colombia’s largest drug trafficking organizations, was wanted by the United States.

The 43-year-old Caicedo Velandia, known as “Don Lucho,” is suspected of being the head of the El Dorado cartel.

Caicedo Velandia was arrested last month at a shopping center in the Argentine capital, but his capture was not confirmed until Thursday, when a U.S. extradition request was received in Buenos Aires.

“Along with the Cali and Medellin cartels, Don Lucho’s is one of the largest Colombian drug trafficking organizations,” federal prosecutor Guillermo Marijuan said.

Colombian police said earlier this week that four major drug traffickers, including Caicedo Velandia, had been arrested in Argentina, Colombia and the United States in an international operation targeting members of a large criminal organization that smuggled drugs and laundered money in several countries.

Caicedo Velandia was carrying a fake Guatemalan passport identifying him as Carlos Martinez Castañeda when he was arrested in an operation conducted by Argentine Intelligence Secretariat agents and DEA agents who had been following him for some time, Marijuan said.

Fingerprints and other information received from the United States confirmed the suspect’s identity, Marijuan told Argentina’s official Telam news agency.

“Some security measures were taken with the suspect” in case his associates tried to get him out of Buenos Aires’s Villa Devoto prison, where he is being held, the prosecutor said.

CIA officers and DEA agents, as well as Assistant United States Attorney Bonnie Klapper, traveled to Buenos Aires after Caicedo Valencia’s arrest.

Argentina received a formal extradition request from the United States on Thursday and a federal court in Buenos Aires will handle the proceedings, Marijuan said.

The suspect’s El Dorado cartel became a leading drug trafficking organization after the dismantling more than a decade ago of the Medellin and Cali cartels by the Colombian government.

Caicedo Valencia has been under investigation by U.S. and Colombian authorities since 2007.

The El Dorado cartel moved drugs and money between the United States and Colombia via ports in Mexico, but Caicedo Velandia had been operating “in recent times” out of Argentina, where he entered posing as a Guatemalan businessman, Marijuan said.

Evidence gathered by U.S. investigators indicates that the cartel earned $180 million between April 2007 and May 2008 alone, the prosecutor said.

“To give you an idea of how big this case is, the extradition request for Caicedo Velandia has two parts, which deal with multiple transactions,” Marijuan said.

The prosecutor said he was working with federal Judge Julian Ercolini “to comply with the extradition request” filed by the United States. EFE