Congolese and Rwandan forces launched joint operations in January 2009, to eliminate the threat caused by a terrorist group, Democratic Forces for the Liberation of Rwanda (FDLR), based in the DRC.
The joint operations weakened the militias but it did not destroy them.
The fighters are a hodge-podge of former participants in the 1994 Genocide against the Tutsi and young men recruited from refugee camps in Congo.
The group has since last year been "regrouping and reorganising" to attack Rwanda.
Reports, including one by UN peacekeeping mission in DRC (MONUSCO), say that 4,000 recruits or "FDLR cadres" had regrouped in North Kivu, with some coming from as far as Zambia.
According to the Military and Defence spokesperson, Brig. Gen. Joseph Nzabamwita, FDLR's renewed impetus started in April 2012 when the security situation in eastern DRC worsened following renewed fighting between Congo government forces (FARDC) and the M23 rebels.
"This is when the DRC government started giving the FDLR political freedom and room for maneuver, rearming them, and facilitating alliances or working relationships between them [FDLR] with other militia groups created by the government of DRC, such as the Mai-Mai Nyatura, a [Congolese] militia group in Masisi, as a strategy of countering the M23," Brig. Gen. Nzabamwita told The New Times in an interview.
With the support of the Congolese army (FARDC), the FDLR which had previously been weakened, was able to rapidly move within striking distance from the Rwandan border.
"They are regrouping and reorganising, both in South Kivu and North Kivu, with the intention of attacking and destabilising Rwanda. The forces that used to be scattered were now brought together and they have benefited from the support of FARDC since April 2012," the spokesperson added.
The FDLR are allegedly already operating in the North Kivu provincial capital, Goma, in the blanket cover of the 41st Battalion of FARDC. Others are operating in areas of the city including Mudja, Rusayo and Kanyati.
Among others, an FDLR battalion commanded by Lt. Col. Ezra Kalebu is reported to be operating in the localities of Kishishi, Kibirizi, Bambo, Mubambiro, Sake, Kiroche, Ishasha and Minova. In all these places, the FDLR has full FARDC backing, he added.
In November and December, last year, the rebels launched attacks on Rwanda but were repulsed by the Rwanda Defence Forces.
On November 27, 2012, about 120 FDLR elements crossed into Rwandan territory, killed a civilian and injured four others, in a village called Muti, in Rubavu, Western Province.
Five days later, on December 2, they struck again, in Kinigi, killing a park warden attached to the Volcanoes National Park in Musanze District and wounded another.
Ever since the two incidents, security was beefed up in the border areas and no other incident has been reported since.
Rwanda would on no account be drawn into the conflict in the eastern DRC though the army remains on standby to repulse any violation of Rwandan territory by the FDLR, Nzabamwita emphasized.
Returnees' homeward influx
In the midst of the present chaos, however, the FDLR and hundreds of their dependents, in South Kivu, had to move. Deadly clashes with one of the local Congolese Mai-Mai Raïa Mutomboki group, opposed to the FDLR criminal activities against innocent Congolese, caused this movement. The FDLR are fleeing from Raïa Mutomboki in Shabunda and Kalehe areas among others.
"They (FDLR) are particularly supported by Brig. Gen. Masunzu, the commander of the FARDC South Kivu military region. There is a high-level alliance," Brig. Gen. Nzabamwita said, explaining that the militia group has been moving their "cadres and fighters" to safer places in South Kivu, with FARDC's help.
Some fighters and civilians reportedly use this as a rare break to escape and return home to Rwanda even though during this repositioning and exodus, among other things, the FDLR's primary objective is the 'protection' of its dependants and cadres.
The group, which is known to keep a tight leash on its civilian dependants - actually keeping them hostage - will, reportedly, kill anyone caught trying to escape and return to Rwanda. However, in recent months, there has been a rare surge in the number of returnees - civilians and combatants.
In the first weeks of January alone, over 200 refugees or FDLR civilian dependants returned home. In the same period, over 120 ex-combatants returned.
According to the Chairperson of the Rwanda Demobilisation and Reintegration Commission (RDRC), John Sayinzoga, MONUSCO helped repatriate a total of 127 low rank ex-combatants in the first week of January 2013. Sayinzoga says the figure is "a slight" increase and not necessarily a huge number.
Sayinzoga said, "During their movements, some of the civilians outwit their escorts and plan such that members of their families can flee and return to Rwanda, especially nowadays that they have information about the peaceful situation back home. They are smart."
Given the FDLR's threats, Brig. Gen. Nzabamwita is confident of RDF containing the threat.
"Even a single terror attack is a threat. We are able to contain the threat but containing it when they are busy regrouping and reorganising freely in eastern DRC with the kind of support they are getting is a very big constraint. Our only option is to be prepared, and, we have security plans. When they come, definitely, we will deal with them but we wouldn't want that because even one single collateral damage is not wanted."