KILIMANYOKA, Congo - Rebels vowing to take Congo's eastern provincial capital advanced toward Goma on Tuesday, sending tens of thousands fleeing. The top U.N. envoy said government soldiers had fired on civilians and foreign aid workers trying to escape the region. Alan Doss, the top U.N. envoy in Congo, said peacekeepers were forced to "respond" after government soldiers fired on civilians and trapped foreign aid workers trying to leave Rutshuru, a strategic town north of Goma. He vowed to keep Rutshuru and other towns out of rebel hands. "We are going to remain there, and we are going to act against any effort to take over a city or major population center by force," he told reporters in New York in a videoconference.

Aid agencies said their workers could hear bombs exploding as the rebels closed in and angry and frightened civilians and soldiers blocked their evacuation by U.N. peacekeepers.

The mob was looting humanitarian centers and the belongings of about 50 trapped aid workers in Rutshuru, said Ivo Brandau, a spokesman for the U.N. humanitarian agency OCHA.

Brandau said tens of thousands of civilians were fleeing that town, heading north and east toward the Ugandan border. Rutshuru had a population of about 30,000 residents and the same number of refugees.

Doctors Without Borders said its doctors and nurses trapped at Rutshuru Hospital had treated 70 war wounded since Sunday but most patients had fled the hospital.

Meanwhile, a sudden influx of an estimated 30,000 people tripled the size of a camp in Kibati in a matter of hours, said Ron Redmond, spokesman for the U.N. refugee agency.

"It's chaos up there," Redmond told The Associated Press from Geneva, citing U.N. staff in Congo. "These crowds of people coming down from the north have already started turning up there."

The unrest in eastern Congo has been fueled by festering hatreds left over from the Rwandan genocide and the country's unrelenting civil wars. Renegade Gen. Laurent Nkunda has threatened to take Goma despite calls from the U.N. Security Council for him to respect a cease-fire brokered by the U.N. in January.

Nkunda charges that the Congolese government has not protected his minority Tutsi tribe from a Rwandan Hutu militia that escaped to Congo after helping perpetrate the 1994 Rwandan genocide. Half a million Tutsis were slaughtered.

Nkunda's ambitions have expanded since he launched a fresh onslaught on Aug. 28 - he now declares he will "liberate" all of Congo, a country the size of Western Europe with vast reserves of diamonds, gold and other resources. Congo's vast mineral wealth helped fuel back-to-back wars from 1997 to 2003.

The U.N. says more than 200,000 people have been forced from their homes in the last two months, joining 1.2 million displaced in previous conflicts in the east. Outbreaks of cholera and diarrhea have killed dozens in camps, compounding the misery.

On Monday, peacekeepers in attack helicopters fired at the rebels trying to stop them taking Kibumba, a village on the main road 30 miles north of Goma. But fleeing civilians say the fighters overran Kibumba anyway.

The rebels retaliated by firing a missile at one U.N. combat helicopter Monday, but missed, U.N. spokeswoman Sylvie van den Wildenberg said.

In Kibati, a few miles from the front line, young men lobbed rocks Tuesday at three U.N. tanks also heading away from the battlefield. The U.N.'s peacekeeping mission is the agency's biggest in the world, with 17,000 troops.

"What are they doing? They are supposed to protect us," said Jean-Paul Maombi, a 31-year-old nurse from Kibumba.

U.N. efforts to halt Nkunda's rebellion are complicated by the country's rugged terrain, dense tropical forests that roll over hills and mountains with few roads.

On Tuesday, a U.N. official who spoke on condition of anonymity because of the sensitivity of the subject said rebels in civilian clothes made several attempts to infiltrate Goma, but U.N. peacekeepers spotted them and forced them to return.

Also Tuesday, a U.N. helicopter gunship patrolled the sky in Kilimanyoka, 7 miles north of Goma. Rebel spokesman Bertrand Bisimwa said he expected the helicopters to soon attack their front line, which he said is within 12 miles of Goma.

The U.N. spokeswoman said U.N. attack helicopters were trying to impede the rebels and they appear to have succeeded in part Tuesday. In late afternoon, about 200 government soldiers were nearly two miles closer to the rebels than the line of the troops that retreated. They were being resupplied from a truck loaded with rocket-propelled grenades.

The chief U.N. mandate is to protect the population. But since the peace deal it also is supposed to help the Congolese army disarm and repatriate Hutu militiamen - by force if necessary.

But Bisimwa, the rebel spokesman, claimed Tuesday the Congolese army has abandoned dozens of its positions to Hutu militiamen.

"It's the Hutus who are on the front line and whom we are fighting, not the army," he said. U.N. peacekeepers "leave us no choice but to fight on."

Also Tuesday, a U.N. helicopter gunship patrolled the sky in Kilimanyoka, 7 miles north of Goma. Rebel spokesman Bertrand Bisimwa said he expected the helicopters to soon attack their front line, which he said is within 12 miles of Goma.

The U.N. spokeswoman said U.N. attack helicopters were trying to impede the rebels and they appear to have succeeded in part Tuesday. In late afternoon, about 200 government soldiers were nearly two miles closer to the rebels than the line of the troops that retreated. They were being resupplied from a truck loaded with rocket-propelled grenades.

The chief U.N. mandate is to protect the population. But since the peace deal it also is supposed to help the Congolese army disarm and repatriate Hutu militiamen - by force if necessary.

But Bisimwa, the rebel spokesman, claimed Tuesday the Congolese army has abandoned dozens of its positions to Hutu militiamen.

"It's the Hutus who are on the front line and whom we are fighting, not the army," he said. U.N. peacekeepers "leave us no choice but to fight on."

Nkunda long has charged that Congolese soldiers fight alongside the militia of Hutus, an ethnic majority of about 40 percent in the region.

Some 800 Hutu militiamen have voluntarily returned to Rwanda, the U.N. says, but the fighters recruit and coerce Congolese Hutu children and young men into their ranks daily - far outnumbering those who have returned home.

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Associated Press writers Edith M. Lederer at the United Nations and Alexander G. Higgins in Geneva contributed to this report.

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On the Net:

The U.N. mission in Congo: http://www.monuc.org

Written By MICHELLE FAUL

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