Rival ethnic groups battled outside a U.N. compound Wednesday, killing 10 civilians — including women and children — who tried to crowd into the base where thousands of terrorized people have taken refuge. Congo (search) appealed for international troops to end a week of bloodshed.

Overwhelmed U.N. troops from Uruguay fired in the air to ward off the ethnic groups.

"There's firing everywhere, from mortars, Kalashnikovs and other heavy arms," U.N. spokeswoman Patricia Tome said by telephone from the compound during the fighting between Hema (search) and Lendu (search) warriors in the streets of Bunia city.

Stray mortar shells and gunfire riddled the compound. One mortar shell hit within 50 feet of the base, wounding 12 people, mostly children, Tome said.

A mortar shell also killed 10 people and wounded 100 others in a building next door to the compound, said Michel Kassa, a U.N. coordinator of humanitarian affairs.

"The people who were killed were in a building alongside [the compound], which has become the only place where people could huddle for protection. There were lots of people," he said. "I only saw civilians, poor women killed with their babies."

More than 10,000 residents have sought refuge in the U.N. compound and an airport.

Bloodletting flared after May 7, when neighboring Uganda pulled out the last of its 6,000 troops in the area, warning it was leaving a security vacuum behind. The pullout came as part of a multinational military withdrawal following a five-year, six-nation war in the central African country.

The withdrawal left Bunia in the hands of local Lendu fighters, a 625-member U.N. force and an even smaller Congolese police force — no match for the tens of thousands of tribal fighters massed around Bunia, capital of east Congo's lawless Ituri province.

Hema warriors managed to take control of the town Monday. Lendu fighters launched a counterattack Tuesday.

Hema and Lendu fighters have a long and bloody history in the province, vying for territory and riches. Clashes in April alone killed more than 1,000.

On Tuesday, two Red Cross workers were shot dead as they tried to collect the decomposing bodies of untold dead in the streets after a week of battles, local human rights workers said. At least 160 people have been killed in the past week, Tome said Tuesday.

U.N. workers were able to send in two planes loaded with water purification systems, tents and other relief goods Tuesday. Eighty percent of the city's 90,000 people already had fled, Tome said.

Congo President Joseph Kabila flew to internationally brokered talks with Bunia's militia leaders, due to start Thursday in the Tanzanian city of Dar es Salaam, Tanzanian authorities said.

In Kinshasa, Congo's capital, government spokesman Kikaya Bin Karubi appealed to the United Nations to send in an intervention force — rather than the observation force now in place.

"It's truly urgent because the Ugandans and the Rwandans have left in place their militias, to kill each other, and exterminate the Congolese people," the spokesman said.

Uganda and Rwanda and their rebel allies held eastern Congo during the war. Congo accuses Rwanda of backing the Hema warriors, which Rwanda denies.

The United Nations has appealed to France and other governments to contribute troops to intervene against the fighting. France said Tuesday it was considering a request to send a battalion.

At the United Nations, the chief U.N. war crimes prosecutor warned Tuesday that fighting in the region could escalate.

"Our evaluation of what we know — it could be a genocide," said Carla Del Ponte, who is in charge of prosecuting perpetrators of the 1994 genocide in neighboring Rwanda and those responsible for war crimes and crimes against humanity in the former Yugoslavia.