Colombia rebel group and other illegal organizations are moving into FARC-controlled territory ahead of the guerrilla group’s pending demobilization, reported newspaper El Tiempo on Monday.

According to the newspaper, particularly the ELN has been making territorial expansion efforts at the same time the group is engaged in preliminary peace talks with the administration of President Juan Manuel Santos.

The FARC, which successfully has concluded peace talks, is set to begin its demobilization and disarmament process after formally signing peace on September 26.

El Tiempo reported that the FARC has stopped charging “taxes” in areas under its control as the group recently announced.

But instead, the ELN and neo-paramilitary groups are now charging these taxes, sometimes reportedly with detailed information on who previously paid the FARC.

In Anori, Bajo Cauca, citizens used to pay tax to the FARC’s 36th Front. Now, locals told the newspaper “new people from the ELN” have arrived to charge the same tax.

In Catatumbo, a lawless region in the northeast of the country where a myriad of groups operate, locals used to pay extortion payments to the FARC’s 33rd Front. This is now done by the ELN’s Northeastern Front, according to El Tiempo.

Both Bajo Cauca in Antioquia and Catatumbo in Norte de Santander are major coca growing regions that have long been largely abandoned by the state.

Elsewhere in the country, particularly in the southeast and the center of the country, paramilitary successor group Gaitanista Self-Defense Forces of Colombia (AGC), a.k.a. “Los Urabeños,” has nearly doubled its territory in the years the FARC was negotiating peace.

El Tiempo reported similar territorial incursions by group like the ELN and the AGC in Nariño, Cauca, Choco and Guaviare, all traditional areas where the FARC used to exercise almost absolute control.

All of these areas have been flagged as post-conflict risk areas because of the threat illegal armed groups other than the FARC could try to take over the guerrillas’ control over illegal armed activity like drug trafficking and illegal mining.

In Tumaco, Nariño, an important drug trafficking port in the southwest of the country there appears to be a large presence of the AGC.

Hundreds were displaced earlier this year as the group fought with the FARC, won, and took over the area that is infamous for being Colombia’s primary coca growing region with direct access to the Pacific Ocean.

The AGC is also reported to be collecting protection money in the Cauca department, another FARC stronghold.

The group, formed by paramilitaries who refused to demobilize with their AUC group between 2003 and 2006, is extorting middle class families and businesses, by threatening children, parents, and spouses.

Between January and July of this year, 73 murders were reported in the area. Last week, unknown armed men almost randomly assassinated five people in an apparent attempt to violently impose authority.

The territorial moves by Colombia’s remaining armed groups are a major threat to peace in the event Colombia ratifies peace with the FARC in a referendum on October 2.

The president has insisted the government has a “detailed plan” to attack such groups “attempting to fill the gaps left by the FARC.”

At least 16,000 men are being assigned to the task of providing security during the demobilization period and assume the territorial control now in hands of the FARC.

Preceding this mass territorial expansion by the state, more than 100 members of paramilitary successor groups were arrested throughout the country over the weekend.

In addition to the security that will surround the demobilization zones, the army will use 28 battalions in order to provide security and bring state authority to areas where the FARC previously held sway.

However, the army and the police is unable to enter these areas until peace with the FARC becomes effective and an informal exchange of territorial control takes place while FARC guerrillas move into concentration camps where they will disarm.

Colombia’s remaining illegal armed groups don’t have to wait for any protocolary act and can already move into territory controlled by the FARC, whose members are hardly likely to risk their lives in combat while their peace deal is only weeks away.

Sources