The withdrawal of Ugandan troops left a power vacuum
The sound of heavy artillery is again being heard out in the north-eastern Democratic Republic of Congo town of Bunia.
On Monday, an ethnic Hema militia took the town from their Lendu rivals, who now say they are trying to retake the town.
The United Nations Security Council has been discussing sending more peacekeepers to the volatile Ituri district, around Bunia.
France has offered to contribute troops but the Hemas say they would consider French troops as enemies.
Floribert Ndjabu Ngabu, leader of the Front of Nationalists and Integrationists Lendu militia told the French news agency, AFP,
that his troops had launched a counter-attack on Bunia on Tuesday.
A local human rights group, Justice Plus, said that residents had identified 112 people who had been killed during the week-long clashes.
Congolese Human Rights Minister Ntumba Luaba had to seek refuge at UN premises, reports the Associated Press news agency.
Mr Luaba was last year held hostage for a week by Hema militants in Bunia before being released unharmed.
Some officials have likened recent killings and racial tensions in the area to the start of the Rwandan genocide of 1994.
During the first day of talks at the UN on Monday, the head of UN peacekeeping operations, Jean-Marie Guehenno, warned that without decisive action there would be a bloodbath in DR Congo's Ituri province - between the Lendu majority and the Hema minority.
Militias from the two ethnic groups have been battling for control of the town of Bunia since Ugandan soldiers withdrew last week under a peace agreement.
There has been mounting criticism of the UN force, which has more than 600 troops in Bunia.
On Sunday, Ugandan President, Yoweri Museveni, condemned the force (Monuc) as "dangerous tourists".
"The peacekeepers are on alert," said UN spokesman Mamadou Bah.
Security Council President Munir Akram says that a final decision on what should be done in DR Congo is not expected to be reached until later this week.
Council members have been discussing a range of options, from the reinforcement of the existing peacekeeping force in DR Congo, to the deployment of a small, but highly robust foreign force, acting with the UN's blessing.
Thousands have fled into Uganda from Bunia
"France is ready to contribute to the stabilisation of Ituri and right now we are studying ways of taking part in an international force," foreign ministry spokesman Francois Rivasseau said.
But Thomas Lubanga, leader of the ethnic Hema militia, the Union of Congolese Patriots (UPC) said the French would not be welcome because they back Congolese President Joseph Kabila.
"If they are sent, we would consider them as enemies," he said.
Most of the town's population of 300,000 has fled the fighting but some 10,000 have sought shelter in or around UN premises.
One man who had spent last night there said he feared cholera would soon break out. There are no toilets, not much food and water, and no shelter for the population.
When he returned to his home on Tuesday morning, he said everything had been stolen by the UPC fighters.
The Kinshasa government sent 600 special police to Bunia when the Ugandan army started its pullout, but only 100 remain. The rest have all fled.
The Hemas and Lendus have long clashed over land and other resources.
An estimated 50,000 people have been killed in recent years.