Colombian police claim to have arrested the FARC guerrilla responsible for finances and drug smuggling operations across the country’s Eastern Plains and into Venezuela, as the rebels struggle to regroup after the death last year of their field marshal ‘Mono Jojoy.’

Police in Bogota said April 11 that they had arrested Pablo Emilio Rodriguez, alias “Manuel” or “Pata Palo,” who reportedly became manager of the Eastern Bloc’s finances following the death of Victor Julio Suarez Rojas, alias “Mono Jojoy,” during an aerial bombardment in September last year.

Rodriguez is believed to have worked for many years alongside Mono Jojoy’s brother, Noe Suarez Rojas, alias “Grannobles,” who operates in Arauca, along the border with Venezuela. It is through this part of the border that much of the cocaine produced in Colombia’s Eastern Plains is moved into Venezuela, now a key transshipment route, particularly for drugs heading towards Europe. It is no coincidence that when detained Rodriguez produced a Venezuelan identity card.

If Rodriguez was running all Eastern Bloc drug operations and finances, it would be a promotion of the new Bloc commander, Jaime Alberto Parra, alias “El Medico.” El Medico is trying to establish his authority over the Eastern Bloc, the most disperse and powerful of the FARC’s fighting divisions. He is also trying to rebuild finances, especially the FARC’s drug running networks, intelligence sources told InSight.

Mono Jojoy was the second most powerful commander in the Revolutionary Armed Forces of Colombia (Fuerzas Armadas Revolucionarias de Colombia – FARC). He was best known as a military tactician, and oversaw some of the FARC’s boldest offensives against the security forces in the 1990s, such as the taking of jungle town Mitu in 1998, which involved almost 2,000 guerrillas. He died in September 2010 after the air force dropped seven tons of explosives on a rebel camp, an event widely seen as evidence of the FARC’s growing military weakness.

El Medico, in contrast, is better known as the FARC’s doctor than as a leader on the battlefield. Unlike Mono Jojoy, who rose through the ranks due to military prowess, El Medico trained as a doctor in Cuba and built up the FARC’s medical infrastructure, training combat medics. Since assuming Mono Jojoy’s place last September, he has focused on recomposing the Eastern Bloc in their traditional stronghold, the department of Meta. Among his many challenges is commanding the same kind of troop loyalty that Suarez inspired within the FARC. This probably would explain why El Medico would have reshuffled the Eastern Bloc’s internal ranks, promoting new faces like the recently arrested Rodriguez.

El Medico has also reportedly asked the commander of one of the Eastern Bloc’s most powerful units, the 43rd Front, to assume further responsibility for the drug trade in the region. Gener Garcia Molina, alias “Jhon 40,” was demoted under Mono Jojoy, who reportedly wanted to punish him for his womanizing and drinking.

Jhon 40 has kept a low profile since he was reportedly wounded in an aerial bombing in 2008. But if Parra has tasked him with building up the Bloc’s drug business again, this may indicate he is seeking to empower his own circle of confidants, rather than preserving the continuity built under Mono Jojoy.

In another key appointment by El Medico, he has reportedly asked seasoned guerrilla commander Jairo Gonzalez Mora, alias “Byron Yepes,” to take control of the 27th Front, another one of the Eastern Bloc’s stronger units. Parra was previously charged with running some of the FARC’s urban militias in Bogota.

This could indicate that, while Parra is intent on appointing new leadership within the Eastern Bloc, he does not intend to ease up on military operations. While the Bloc is no longer capable of taking over towns with a 2,000-strong force, as occurred at the peak of rebel power under Mono Jojoy, they have readily adapted to more classic, hit-and-run style guerrilla attacks. These include bombing infrastructure, burning buses, and sniper attacks on the security forces. Under this new offensive style, the rebels operate in small, mobile groups, a far cry from the large encampments and ambitious military raids seen under Mono Jojoy.

So far El Medico has not adopted any radically different strategies from his predecessor. The trends we are seeing this year — the shifting of military activity to central and western departments like Cauca, Tolima and Huila, where top commander “Alfonso Cano” is based — were already in motion before Mono Jojoy was killed. While Mono Jojoy built the Eastern Bloc into the fiercest fighting arm of the FARC, now, that role has now been assumed by the FARC’s Joint Western Command.

El Medico does not look prepared to reverse that trend, but nor has the Eastern Bloc stopped offensive actions against the security forces. The FARC’s doctor may yet prove to be a battle-ready leader.