About 200 people may have been killed by Sudanese militias allied with the Rapid Support Forces, after the group that’s fighting for control of the nation overran an army base in the western Darfur region, humanitarian officials said.

The clashes that took place Nov. 4-6 mark a renewal of fighting between the Arab Rizeigat and African Masalit ethnic groups that has flared for decades in Sudan, especially in the West Darfur state capital, Geneina. In June, more than 500 people were confirmed dead in Darfur in fighting between Sudan’s army and the RSF.

“Reports received indicate that the Arab militias killed a number of civilians and injured many others,” United Nations spokeswoman Florence Marchal said in a statement on Wednesday. “These killings were targeted at the Masalit community,” she said, adding that “serious human rights violations” were committed during the attacks.

The militias arrested and detained an unspecified number of people suspected of collaborating with the Sudanese Armed Forces, or SAF, before their base was taken over by the RSF, Marchal said.

Confirmation of the violence came a day after mediators at peace talks in Jeddah, Saudi Arabia, said both sides failed to commit to a cease-fire in a civil war that erupted in the North African country in mid-April. The conflict has left more than 9,000 people dead and forced about 5.8 million others to flee their homes, while the UN estimates about half of Sudan’s 46 million population needs humanitarian assistance.

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Human-rights officers are in the process of documenting the number of victims in the Geneina attacks. Humanitarian officials briefed on the events, who asked not to be identified as they’re not authorized to speak to the media, said an estimated 200 people were killed.

A fugitive SAF soldier, Omer Osman Musa, who reached the Adra refugee camp in neighboring Chad on Tuesday, said the fighting left hundreds of soldiers and civilians dead. Rizeigat fighters attacked the SAF forces with “advanced weapons, especially drones and heavy artillery,” he said by phone.

Sudan’s army has lost control of the vast majority of the western Darfur region in recent weeks, according to conflict monitors and diplomats briefed on the conflict. However, the army still controls the east of the country and Port Sudan, which has access to the Red Sea and has become a defacto base for the government outside of the capital, Khartoum.

The RSF denied specifically targeting civilians.

“As the military zone is located amid residential areas, these actions did unfortunately result in the displacement of civilians,” it said in an emailed statement, adding that since the violence, “no further acts of aggression or armed conflict” had been reported and residents have returned.

Mohamed Hamdan Dagalo, the head of the RSF, who is more commonly known as Hemedti, said in a written statement to Bloomberg, that he wanted a civilian administration to run society after his forces control territory.

“Upon liberating these areas, we promptly call on local civilian administrations to take responsibility for their own affairs,” he said. “The RSF is unwaveringly committed to working with the people to build a new Sudanese state grounded in the principles of peace, democracy, rule of law, and inclusivity.”

(Updates with comment by RSF from ninth paragraph)