TONGO, Congo — Tutsi-led rebels tightened their hold on newly seized swaths of eastern Congo on Saturday, forcing tens of thousands of frightened, rain-soaked civilians out of makeshift refugee camps and stopping some from fleeing to government-held territory.
Aid organizations said they were increasingly worried about a lack of food and shelter.
European officials offered sympathy but no concrete promise of military reinforcements for the Congolese troops and U.N. peacekeepers routed by rebel forces in the sudden escalation of eastern Congo's civil war in the past week.
The rebels appeared to be maintaining a unilateral cease-fire they declared a day earlier, focusing on consolidating territories that stretch to the doorstep of the provincial capital, Goma, instead of taking the city.
The rebels, who said people were leaving the refugee camps of their own free will, asserted that they stopped short of Goma in hopes of stopping the chaos that had engulfed it as government troops fled along with tens of thousands of refugees.
Goma is the site of rebel leader Laurent Nkunda's greatest defeat, when U.N. attack helicopters fired on his fighters advancing on the city in December, killing hundreds of them. It was not clear if that experience influenced his decision.
The area that Nkunda has seized is rich in minerals and agriculture, and commands much of the access to the Rwandan and Ugandan borders.
Britain's minister for Africa said that Britain could send troops if the cease-fire fails but that the first reinforcements should be soldiers deployed elsewhere in the country with the U.N. force, known by its French acronym, MONUC.
British Foreign Minister David Miliband, who came to the region with French Foreign Minister Bernard Kouchner after the outbreak of fighting, downplayed the possibility of a European Union peacekeeping force.
"Nothing is being ruled out," he said in the Rwandan capital after leaving a refugee camp outside Goma. "But we have a 17,000-strong MONUC force, and that is of course the first call for security support in the Congo."
Kouchner said his government was committed to humanitarian assistance, but not necessarily sending in troops. "I repeat, 17,000 soldiers are already deployed."
In Rutshuru, a large town 45 miles north of Goma, two groups of refugees hefted bundles of belongings as they plodded home. Some said they were forced by the rebels to leave camps.
"They beat us with sticks and told us that we must get out," said Daria Nyarangaruye, a silver-haired woman with a rosary around her neck and a spent bullet in her hand.
Nyarangaruye said she had been forced on Saturday to leave a camp near peacekeepers in Tongo, a hilltop town in the shade of volcanic Mount Nyirangano. She spoke near her home 6 miles from Rutshuru.
Rebels were seen blocking civilians who wanted to cross front lines to return to government-held areas.