The M23 group has been ravaging the North Kivu region since April, after a mass defection by former rebel combatants serving in the Congolese armed forces, known as FARDC. It has taken towns including Ntamugenga, Rubare and Bunagana, displacing 300,000 civilians.
Government troops have struggled to contain the group, and six months on, they are talking to local paramilitary groups in the hope of building alliances against M23.
To date, the government of the Democratic Republic of Congo, DRC, has publicly refused to enter into negotiations with the M23 group. But informal talks have taken place behind the scenes, and some analysts think the government might be prepared to make significant concessions to stop the fighting.
If that happens, observers say, offering rebel combatants the same deal as before - integration into the regular army - would not be a good option, as it would simply delay rather than halt the cycle of violence.
M23 is named after a March 2009 deal under which the National Congress for Defence of the People, CNDP, a Tutsi-dominated group in North Kivu with close ties to Rwanda, renounced its paramilitary force while its political wing joined the mainstream. Two years later, the CNDP backed President Joseph Kabila's successful bid for re-election in 2011. The CNDP combatants were drafted into the Congolese national army, and their commander Bosco Ntaganda was made a general.
M23 arose when Ntaganda led many of his ex-CNDP men out of the army in a mutiny in spring 2012. The causes were twofold - first, the DRC authorities had been trying to break down the paramilitary structures that continued to exist within the army by deploying commanders outside their home areas. Second, the government was under increasing pressure to arrest Ntaganda, who was subject to indictment by the International Criminal Court in The Hague on charges of murder, rape and conscripting child soldiers, dating to a time when he led another militia. (See also With Focus on One DRC Rebel Chief, Others Forgotten.)
Service in the regular army has helped M23's leaders gain the upper hand since they went back to life as rebels. Thanks to the experience they accumulated during their time as FARDC officers, they know how the army thinks and operates, and they have been able to set up an intelligence network that provides them with real-time information about military operations against them.
"There are [pieces of] information that reach the rebels, they know our operations and movements because of traitors in our ranks," a serving FARDC major told IWPR on condition of anonymity. "Even our best trained troops stand no chance in this context."
Six months on from the start of the M23 insurgency, both sides seem ready to explore the possibilities for some kind of peace deal.
The rebels are backing their offer with threats. M23's political leader, Jean-Marie Runiga, said last month that "if the government does not come to the negotiating table, we will have to defend ourselves".
The DRC government has publicly maintained that it will not negotiate with M23. But discreet, indirect talks have taken place, mediated by the Ugandan government in Kampala.
"The Congolese government has informally contacted the M23 through the Ugandan government, but is not optimistic about finding a compromise," said Jason Stearns, an analyst on DRC who has led a United Nations investigation into the violence in the Kivus.
If a deal were to take shape, one obvious way of soaking up large numbers of combatants would be to reintegrate them back into the FARDC. But that route has already been tried, and it manifestly failed with the mass defections this spring.
"Resorting to the old solution of integrating rebel forces without breaking down their command structures, and rewarding them with senior command positions and key strategic deployment zones can put an end to the current fighting, but it will produce more violence in the long run," Maria Eriksson Baaz, senior researcher at the Nordic Africa Institute, told IWPR.
As well as a core of regular troops, the FARDC has come to embrace a patchwork of militias that act on the orders of local commanders, many of whom show little loyalty towards the central government in Kinshasa. After the integration of CNDP forces in 2009, high-ranking officers like Ntaganda and Sultani Makenga - now also a top M23 leader - posed a constant challenge, since it was they rather than the FARDC command who made key decisions about operations and troop deployment in eastern DRC.
"In effect, there were two branches in the army, one operating under the command of General [Gabriel] Amissi, the chief of army staff, and one operating under Bosco Ntaganda's command," Marc-André Lagrange, senior analyst at the Brussels-based think tank, International Crisis Group, said.
The resulting parallel structure left Ntaganda with a lot of power. A report by UN experts released in January 2012 said that Ntaganda had a share in major businesses in the region, and that no military decision could be made without his authorisation.
The Kinshasa government failed to ensure that integration was carried through in a thorough manner, nor did it act to rein in wayward commanders.
Judith Verweijen, researcher at Utrecht University's Centre for Conflict Studies, sums up the government's past approach to dealing with the CNDP as "carrots without sticks".
"The policy towards armed groups has been generally one more of persuasion than pressure," she said. "This creates very skewed incentive structures in an army, as troops constantly see that those breaking the rules are being rewarded."
As Verweijen notes, the handling of the 2009 integration process had a demoralising effect on loyal FARDC officers, who saw former rebels granted privileges denied to them.
This resentment led to tensions, and in September 2011, two months before the presidential election, a group of FARDC officers who had never been part of a rebel group threatened to mutiny in protest against the preferential treatment accorded to colleagues drafted in from the CNDP.
"How can they be rewarded for fighting against us? They now have higher ranks and beautiful houses. That is not fair; it makes us think that our leaders are not patriots," said a captain in the Congolese army interviewed by IWPR in November 2011.
Repeating this kind of reintegration in order to neutralise M23 would only further undermine morale by sending a message that betrayal, not loyalty, is the most successful strategy.
"When there is repeated high treason, there are measures that must be taken," an army major, speaking on condition of anonymity, told IWPR. "When someone betrays several times and still is taken back into our ranks, what can we understand? They are rewarded for their bad behaviour."
Despite the misery the M23 insurgency has inflicted on the population of eastern DRC, Colonel Olivier Hamuli, the FARDC's spokesman in North Kivu, sees the rebellion as a necessary evil, since it resulted in disloyal elements identifying and removing themselves from the military.
"I think [this mutiny] is a good thing for Congo. It is painful, but at least all those who are not for the republic are getting exposed," Hamuli said.
Another challenge to FARDC cohesion is the fact that quite apart from M23, other senior army members have defected in recent times to set up insurgent groups fighting government forces in eastern DRC. Experts say this is further proof that integration is not a viable solution for dealing with combatants either from the CNDP or other groups.
"Many FARDC commanders have deserted between 2009 and 2012, and reconstituted smaller or larger armed groups or renegade units. This shows that the problem is endemic, and involves commanders from all different backgrounds," Eriksson Baaz said.
Verweijen cited the example of Nyiragire Khifaru, a commander of the PARECO (Coalition of Patriots in the Congolese Resistance) rebel militia. Khifaru was brought into FARDC, but deserted with 200 troops last year after he was not given a regimental command. Despite his defection, and allegations of human rights abuses, he was later reinstalled in the army, and promoted to regimental commander.
This points to an emerging pattern, Verweijen believes, where defecting and setting up a rebel group is a valid means of advancing one's position.
FARDC is being weakened by the periodic defection of the disloyal, and the demoralisation of loyal soldiers. But this vicious circle has the effect of encouraging the DRC government to consider reintergration as an option for rebels, since the army has less and less capacity to defeat them.
The armed forces have been subject to a number of reform initiatives, mostly led by international donors. But sources interviewed by IWPR say the lack of a unified training programme has exacerbated the problems of poor cohesion and divided command structures, and has failed to bring disparate factions together.
"One unit is trained by the Americans, another by the Belgians, another by the Chinese. They all have different styles and it creates a discrepancy between the units instead of reinforcing them," a British military expert who has served with the UN peacekeeping force in eastern DRC, told IWPR.
The need to absorb a variety of rebel groups, plus the failure to implement comprehensive, focused reforms has, experts say, resulted in a disjointed institution lacking in legitimacy, coherence and unity.
"The government should have defined a framework for integration and created a real structure, but they did not give themselves the means to do this properly," Goyon Milemba, coordinator of the Network for the Reform of the Justice and Security Sector in North Kivu, said. "Instead, they [ex-rebels] were catapulted into the army without training and checking. Not everyone should have been integrated."
Milemba warns that the army reform that is currently so lacking is essential if eastern DRC is to be stabilised and returned to full central government control.
"We cannot develop without first getting a grip on the security system of our country, because no one can talk about development when there is insecurity," Milemba said.
* Mélanie Gouby is an IWPR contributor in Goma, eastern DRC.