GOMA, Congo — A rebel offensive to expel some of the perpetrators of Rwanda's 1994 genocide forced more than 3,000 civilians to flee eastern Congo to neighboring Uganda in a single day, the insurgents and U.N. officials said early Thursday.
In New York, the U.N.'s top Congo envoy told the Security Council that peacekeepers have opened several investigations into whether war crimes are being committed in eastern Congo, pointing to evidence of targeted killings. And U.N. Secretary-General Ban Ki-moon, in a report to the Security Council, recommended U.N. peacekeepers should remain in Congo through 2009.
Rebel spokesman Bertrand Bisimwa said the insurgents began an offensive Saturday in Ishasha border town to push some 1,500 Hutu militiamen, many believed to be Rwandan exiles, out of Congo. Ishasha, on Congo's border with Uganda, is about 35 miles (50 kilometers) northeast of the de facto rebel capital, Rutshuru.
Bisimwa said the rebels were operating in a "lawless" area full of hideouts used by the Hutu militia that is led by Rwandan fighters who fled after helping perpetrate the 1994 genocide that killed more than 500,000 ethnic Tutsis and moderate Hutus.
"There is no government army there," Bisimwa said. "There is only (Hutu militiamen). We wanted to secure our population there. We want this (Hutu militia) to leave this area."
The rebels, led by renegade Congolese Tutsi general Laurent Nkunda, have sworn to hunt down Hutu militiamen hiding in Congo.
At the U.N., Ban's report said, "The forced displacement of populations and evidence of the targeted killings of civilians are alarming. In the current climate, the possibility of massacres of civilians cannot be ruled out."
Bisimwa said the rebels believe there are two battalions of Hutu militia, about 1,500 fighters, in the area. He said the rebels would continue their advance against the militia, which he referred to by their French acronym for the Democratic Liberation Forces of Rwanda.
"We are continuing until we are sure that the FDLR leave all our areas around Rutshuru," he said. "The people who are there, they are afraid of the FDLR and they are taken hostage by the FDLR. These FDLR use the people so we can't shoot them. They take the population and they use them like human shields."
But Congolese civilians who fled to Uganda said "rebels attacked their homes," according to the U.N. refugee agency spokeswoman there, Roberta Russo.
"We have received 3,000 Congolese refugees in the last 24 four hours. We expect more to come in. Some of them said that they have been walking on foot for the last two days," she said from Kampala, the Ugandan capital.
She said more than 16,500 Congolese refugees have fled to Uganda since fighting intensified at the end of August.
Bisimwa said this latest offensive did not constitute a violation of the rebels' unilateral cease-fire. "We said this cease-fire involved only us and this government army," he said.
In a separate development, government officials announced the discovery of two mass graves containing as many as 2,000 bodies in Bukavu, an eastern Congolese city south far from the latest fighting.
Justice Minister Luzolo Bambi told reporters the graves were found Saturday in a plot of land formerly owned by a member of the Congolese Rally for Democracy, a Rwandan-backed rebel group led by minority Tutsis in Congo.
At one point, the Rally controlled much of eastern Congo, but it became a political party in 2003 and many of its top leaders are now integrated in the government, with jobs as vice presidents and army chiefs.
All fighters in Congo have been accused of gross human rights abuses, including the government army.
On Tuesday, New York-based Human Rights Watch charged that Congo's government had killed an estimated 500 opposition members, alleging that Congo's president himself gave orders to crush opponents. The report was the first serious allegation of widespread abuse and possible crimes against humanity by the 2-year-old government.
A presidential spokesman called the report "nonsense."
The report says victims' bodies were dumped in the Congo River and buried in mass graves to hide evidence.
President Joseph Kabila, himself a former rebel leader whose father seized power in 1997 after years of war in Congo, won the country's first democratic election in more than 40 years in 2006.
The report says those assassinated included supporters of Jean-Pierre Bemba, who came in second in the heated 2006 presidential race. Bemba, another former warlord with a large personal army, refused to dismantle his militia, leading to clashes with security forces that left at least 300 dead in March 2007.
Low-level fighting among armed groups has ground on for years in Congo's lawless North Kivu province, but violence sharply escalated in August and has since displaced 250,000 people.
Many of the Hutu extremists who orchestrated the mass killings have remained in Congo, prompting Tutsi-led Rwanda to invade the mineral-rich nation twice. There are fears this latest fighting could again draw in neighbors as in Congo's 1998-2002 war, which brought in armies from six African nations in a greedy scramble for the country's vast mineral riches.
Nkunda fought in Rwanda to end the genocide, then joined rebels in Congo who won power. He quit Congo's army in 2004, claiming he is fighting to protect the country's tiny Tutsi minority. Congo has an estimated 200 ethnic groups, but Hutus are the biggest majority group in eastern Congo.