Violence against civilians in Sudan is “verging on pure evil”, a senior United Nations official has warned, after nearly seven months of war has left a wave of destruction with at least half the population in need of humanitarian aid.

“We continue to receive unrelenting and appalling reports of sexual and gender-based violence and forced disappearance, arbitrary detentions, and grave violations of human and children’s rights,” Clementine Nkweta-Salami, the UN humanitarian coordinator for Sudan, told a news conference on Friday.

“What is happening is verging on pure evil. The protection of civilians continues to be of major concern,” she said.

Since the civil war escalated between the Sudanese army and paramilitary Rapid Support Forces (RSF) in April, nearly six million people have been uprooted from their country or have been internally displaced.

Nkweta-Salami added that some 25 million people need humanitarian help and said that more than 70 percent of health facilities in the conflict areas were now out of service, resulting in outbreaks of cholera, dengue, malaria, and measles, and high levels of malnutrition among children.

The UN is targeting about 12 million people for aid and has appealed for another $2.6bn.

Within Sudan, fears are also mounting that the horrors of Darfur 20 years ago are returning, with reports of widespread killings, rapes, and destruction of villages in the region.

Nkweta-Salami noted that people fleeing to neighbouring Chad had also reported cases of ethnically driven killings taking place in Sudan’s West Darfur with the RSF taking over the main army base in the state capital, el-Geneina.

The RSF is about to take over Darfur entirely from the Sudanese army, according to Mohamed Osman, the Sudan researcher for Human Rights Watch.

He told Al Jazeera that such a takeover could increase atrocities against civilians and added that the UN Security Council has the power to authorize a peacekeeping mission to provide at least minimum protection for civilians, while also helping to monitor abuses and atrocities.

Nkweta-Salami said the UN has heard of crimes against Darfur’s Masalit ethnic community, and said they “are really egregious violations of human rights and it must stop”.