JOHANNESBURG, South Africa -- Rebels in the Democratic Republic of Congo seized the eastern city of Goma with ease on Tuesday, raising fears of a new regional war that could leave tens of thousands of people dead.
Facing little resistance, the M23 rebels also took control of the airport, news agencies reported.
Tensions in the volatile region rose, with Rwanda accusing Congo's army of shelling its territory with tanks and mortar fire while Congolese officials accused the Rwandans of backing the rebellion, a claim supported by the United Nations and analysts.
The occupation of Goma and the retreat of Congolese forces were further evidence of the inability of President Laurent Kabila's government to impose its will on the resource-rich east. The city is much closer to the Rwandan capital of Kigali, about 60 miles away, than to the distant Congolese capital of Kinshasa in the far west.
The crisis also raised questions about the U.N. peacekeeping mission -- the United Nations Organization Stabilization Mission in the Democratic Republic of Congo, or MONUSCO -- which has about 6,700 troops in the region but did not engage the rebels as they marched on the city of 1 million, according to news reports.
"MONUSCO is keeping its defensive positions," Congolese military spokesman Olivier Hamuli told the Associated Press. "They do not have the mandate to fight the M23. Unfortunately, the M23 did not obey the MONUSCO warnings and went past their positions. We ask that the MONUSCO do more."
M23 launched its rebellion in April, defecting from another militia that had been absorbed into the army in a 2009 peace deal. Their main grievance was their claim that the government hadn't lived up to the deal.
Even before the rebels took Goma, M23 leaders such as Bosco Ntaganda exercised significant control in the region, collecting taxes and benefiting from the smuggling of minerals. Ntaganda, nicknamed The Terminator, has been indicted by the International Criminal Court on war crimes charges.
The International Crisis Group, an independent think tank, Tuesday called for the imposition of international sanctions on the rebels and their outside supporters. A leaked U.N. report recently accused Rwanda's defense minister, James Kabarebe, of commanding the M23 forces and said Rwanda and Uganda broke an arms embargo by supplying weapons to the rebels. Both countries deny the accusations.
"Regional and international actors must now prevent this turning into a new regional war," the think tank said in a statement. "The past week has shown history repeating itself in eastern Democratic Republic of Congo, with the same tragic consequences for civilians in the region."
The crisis has severely disrupted humanitarian agencies' work. More than 60,000 people have fled their homes or refugee camps in the recent attacks, but humanitarian agencies warn that worse is to come if the conflict is not resolved swiftly.
Doctors Without Borders said tens of thousands of people living in a refugee camp fled in panic in recent days toward other relief facilities. About 700,000 people have fled the fighting since the beginning of the year, according to aid groups.
Oxfam said the population of eastern Congo was subjected to rapes, attacks, torture, forced recruitment as fighters, forced labor and killings by various armed groups, who also looted, stole and extorted money. The organization Tuesday released a survey of 1,300 people in the region that said various rebel groups and government forces frequently extorted money and goods from the population.
"Ruthless militias and government troops are both mercilessly exploiting local communities to help fund their war,” said Oxfam’s associate country director, Elodie Martel. "This is a humanitarian catastrophe on a massive scale and the world cannot continue to turn its back on this tragedy.”
The International Crisis Group warned that the conflict would lead to an increase in abuses against civilians and killings and could trigger all-out war between Congo and Rwanda. It called on Rwanda to end any military involvement in its neighbor's territory and on the Congolese government to more effectively manage the region and its army in the east.
The region has seen some of the continent's deadliest fighting in the last two decades. Warfare in the 1990s and 2000s at times involved eight regional countries and two dozen militias, leaving more than 5 million dead.
M23 rebels moved on Goma in recent days after the Congolese government refused to negotiate a cease-fire with the group, which had demanded that government forces leave the city.
French Foreign Minister Laurent Fabius said Tuesday it was "absurd" that U.N. forces failed to protect Goma and called for a review of the mission's mandate, Reuters news service reported.
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