"There are sporadic exchanges of fire in the hills around Rumangabo," de Merode said by telephone from the region on Monday. "The situation is very volatile right now."
The fighting petered out by Friday, when rebels handed over the military base to a UN peacekeeping force, which in turn passed control back to the Congolese government.
Even so, tensions remain, because the rebels have only withdrawn a few kilometers and are hiding in the hills around Rumangabo.
Many of the people who fled returned home, but Virunga's park staff are now caring for 600 relatives of the 43 Virunga rangers in a makeshift refugee camp.
Gorillas Under Threat Again
The rebels have occupied much of the Mikeno Sector of Virunga for the last year, preventing the rangers from getting up to the remote area where the gorillas live.
"Things remains much the same as since September last year," de Merode said. "The gorillas remain under rebel-held territory, so we don't have access to them."
In August, however, rangers managed to reach the gorilla area and saw a silverback for the first time in a year—a rare bit of good news in the region.
The combat has renewed fears that the conflict in eastern Democratic Republic of the Congo (DRC) could lead to a wider war.
Rwanda denies that its troops are involved. But the country claims the Congolese military has teamed up with militiamen from Rwanda's Hutu ethnic group who had taken part in the 1994 genocide and later fled into the DRC.
Nkunda says his CNDP is protecting people from the Tutsi ethnic group—who were targeted in the Rwandan genocide—from the Hutu militiamen.
"We still hope that the [CNDP] will come back to the negotiating table and accept its part of the disengagement plan," said Lt. Col. Jean-Paul Dietrich, military spokesman for the UN peacekeeping force in eastern DRC. "But there is no formal approval from CNDP.
"Such a plan only works if all parties agree on the rules."
UN to the Rescue?
Dietrich says the peacekeepers have seen no evidence that Rwandan forces have joined up with Nkunda. Still, figuring out the truth is extremely difficult, because Nkunda's men are known to wear Rwandan uniforms, and many speak the same language—Kinyarwanda—as Rwandan troops.
The eastern DRC has lived under the shadow of war for years. The last several weeks of fighting have dashed hopes that Nkunda's CNDP would adhere to a peace deal that it had signed with government forces in January. Shortly after signing the deal, Nkunda promised to take his fight across the DRC.
The Congolese government wants the UN Security Council to discuss Congo's allegations of Rwandan involvement with the CNDP.
Late last week UN Secretary-General Ban Ki-moon urged the DRC and Rwanda to "bridge their differences using diplomatic and other peaceful means available to them."
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