Is it the end of paramilitarism in Colombia?

• A version of this post ran on the author's site, www.insightcrime.org. The views expressed are the author's own.

Venezuelan authorities have captured the last of Colombia's paramilitary chieftains, marking the end of the United Self-Defense Forces of Colombia (AUC), which dominated the drug trade for over a decade and penetrated all facets of the state.

Hector German Buitrago, better known by his alias of "Martin Llanos," was arrested along with his brother, Nelson Orlando Buitrago, alias "Caballo," in the Venezuelan state of Anzoategui. Martin Llanos headed the Self Defense Forces of Casanare (ACC), a powerful paramilitary faction with over 1,000 fighters in the Colombian provinces of Casanare, Meta and parts of Boyaca and Vichada. The group was founded in the 1980s by the men's father, Hector Jose Buitrago, as a response to guerrilla extortion and kidnapping in Casanare. Hector Jose was arrested in April 2010 in Colombia, while his sons left the country, living in Ecuador and Bolivia before moving to Venezuela. The ACC founder had previously been arrested in 1996, but was rescued from prison by his sons.

Both of the Buitrago sons are wanted in Colombia in connection with murders, forced disappearances, and drug trafficking. Martin Llanos has at least 11 arrest warrants pending, including charges of murder and kidnapping. He has already been condemned to 40 years in prison in absentia. He and the ACC are blamed for the deaths of at least 10,000 Colombians.

The Colombian chief of police, General Oscar Naranjo, said that the arrest of the brothers marked "the end of paramilitarism."

In one of the bloodiest wars between rival paramilitary groups, the ACC and the Centaurs Bloc of the AUC fought each other between 2002 and 2004 for domination of Colombia's Eastern Plains and the lucrative drug trade that moves across them. It is estimated that at least 2,000 fighters on both sides were killed, and hundreds more "disappeared" in that struggle.

I met all three Buitragos in 2003 and 2004, interviewing them in their mountain stronghold in the municipality of Monterrey in Casanare, in the center-east of Colombia. Unlike many leaders of the AUC, who preferred the high life in the cities or luxury haciendas in the countryside, the Buitragos spent much of their time in the mountains, living like the guerrillas they fought. They had strong support from ranchers and local businessmen throughout Casanare, and it was this support, as well as their mountain lifestyle, that allowed them to survive the onslaught by the far stronger Centaurs Bloc, which attacked them with the support of corrupt elements in the security forces.

While most of the AUC surrendered to the government during the peace process from 2003 to 2006, the ACC refused to demobilize, preferring to continue running their criminal empire. This is believed to involve drug trafficking not only on Colombia's Eastern Plains, but into Venezuela and Bolivia. In June last year, Carlos Noel Buitrago, alias "Porre Macho" (in Spanish), was arrested in the Bolivian city of Santa Cruz, where he was charged with running a drug smuggling network linked to his cousin Martin Llanos.

The ACC also got involved in local politics. In the so-called "Pact of Casanare," mayors in the province of Casanare received paramilitary backing during the elections, and in return delivered to the ACC half of their municipal budgets. Six mayors have already been imprisoned as part of the case, as well as a former governor of Casanare, Miguel Angel Perez.

The arrest of the two Buitrago brothers was a result of a joint Colombian-Venezuelan operation. Colombian police had been tracking the two since 2010, discovering that they were residents in Venezuela. They had been following the ex-wife of Nelson Buitrago, which led them to him in to the town of El Tigre, Anzoategui, where the men were arrested. Initially they arrested Nelson, with another man who claimed to be his driver. However the physical similarity between the two men was obvious and authorities suspected they had netted Martin Llanos, which was confirmed after his fingerprint details were sent from Colombia.

These captures are just the latest in a long series of arrests of Colombian drug traffickers in Venezuela. Under pressure from Colombian and US law enforcement, many Colombian drug traffickers have sought refuge in the neighboring country, although the arrest of senior figures like Maximiliano Bonilla Orozco, alias "Valenciano," in November 2011, as well as the Buitrago brothers, reveal it is no longer any kind of sanctuary.

However, it is clear that Venezuela is still home to large numbers of Colombian rebels from the Revolutionary Armed Forces of Colombia (FARC) and the smaller National Liberation Army (ELN). The Venezuelan authorities seem a little more reticent about capturing and deporting guerrilla leaders. Venezuelan authorities arrested FARC commander Guillermo Enrique Torres, alias "Julian Conrado," in May last year, but have been reluctant to send him back to Colombia to face charges. The Colombian government has stated that the FARC commander-in-chief, Rodrigo Londoño, alias "Timochenko," is in the Venezuelan province of Zulia, but he remains at large.

– Jeremy McDermott is a director at Insight – Organized Crime in the Americas, which provides research, analysis, and investigation of the criminal world throughout the region.

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