ABUJA – Rwanda-backed rebels have captured two key cities in Congo’s mineral-rich east in less than a month after a major escalation in their yearslong fighting against overstretched and weakened Congolese forces.

With the support of thousands of troops from neighboring Rwanda, the M23 rebels first took Goma last month before marching to Bukavu this weekend in an unprecedented advance since they took up arms more than a decade ago, further raising fears of regional warfare.

Who are the rebels and what do they want?

M23 is one of about 100 armed factions vying for control in eastern Congo. But unlike the others, they are mainly made up of ethnic Tutsis who failed to integrate into the Congolese army. The group says it is defending ethnic Tutsis and Congolese of Rwandan origin from discrimination, although critics say their Rwanda-backed campaign is a pretext for economic and political influence over eastern Congo.

M23 is being supported with troops and weapons from neighboring Rwanda, according to U.S. and U.N. experts. Rwanda’s longtime President Paul Kagame accuses Congolese President Felix Tshisekedi of overlooking the concerns of Congo’s ethnic Tutsis and ignoring previous peace agreements.

How have they managed to capture more ground?

The M23’s takeover of Goma in North Kivu province witnessed intense fighting with government and allied troops that left bodies lying in the streets and thousands of Congolese soldiers surrendering their arms.

But the rebels apparently had it much easier in Bukavu, 100 kilometers (62 miles) south of Goma, where residents reported Congolese forces fleeing as M23 fighters marched into the city with little resistance.

The reasons for the timing of M23’s “all-out assault” could be the realisation that they faced only limited resistance and were pushing against an open door, the International Crisis Group think tank said.

What is being done to resolve the conflict?

The international community has used mostly the same rhetoric since the latest M23 advance started on Jan. 26, with countries emphatic on dialogue and the rebels’ withdrawal but stopping short of financial and diplomatic pressure on Kigali, as was the case in 2012, when M23 took Goma before pulling out.

A summit of leaders from eastern and southern Africa called for an immediate ceasefire but notably didn’t call for the rebels to withdraw from Goma.

Observers have said the muted international pressure on Rwanda is partly because of the guilt over the failure to intervene to stop the 1994 genocide in Rwanda as well as the country’s evolving stature under Kagame both in Africa and the West.

Murithi Mutiga, Africa director at the ICG, said it’s African countries largely to blame for ignoring the warning signs of the conflict. He said the latest fighting was “a failure of African mediation.”

Unlike in 2012, when they withdrew from Goma in less than a week, the M23 has become more emboldened by Rwanda’s support with troops and weapons, Mutiga added.

Could this escalate into regional warfare?

The conflict has regional complications with the involvement of Congo’s southern and eastern neighbors, whose armies were invited by Tshisekedi when M23 resurfaced at the end of 2021.

Some of Congo’s allies have suffered losses, including South Africa with 14 peacekeepers killed in the fighting for Goma. Authorities in Burundi also say their troops have been attacked by the rebels.

“The risk of a regional confrontation has never been higher,” Mutiga said.

The concerns about an escalation beyond Congo also stem from the country’s wars between 1996 and 2003, when Congo’s neighbors and armed groups fought over access to metals and rare earth minerals such as copper, cobalt, lithium and gold. Up to 6 million people have died during the protracted conflict dubbed “Africa’s world war.”

What is Congo’s government doing?

Tshisekedi, who has threatened his country would fight back, has continued to demand action from the international community, which he says has failed to pressure Rwanda.

Although Congo’s government has said it is open to talks that M23 leaders have also agreed to, authorities in Kinshasa say they must be held within the framework of past peace agreements and not M23’s advance.

On the other hand, M23 is eyeing political power and says it’s fighting corruption and bad governance in areas it now controls. The group has said it is open to “direct and sincere” dialogue to address the root causes of the conflict and enforce a ceasefire only if the Congolese military stops their military campaign in the region.