People displaced from eastern areas of Sudan's al-Jazira state arrive to Gedaref city on October 27, 2024. [AFP]

Paramilitaries in Sudan killed more than 120 people in al-Jazira state, the Health Minister said on Monday, after the UN secretary general warned Sudanese are living a "nightmare".

The paramilitary Rapid Support Forces (RSF) have been at war with Sudan's regular army since April 2023 but for about the past week have intensified their violence against civilians in al-Jazira, south of the capital Khartoum, after their commander in the state defected to the army.

"The Rapid Support Forces militia committed a massacre against the citizens of al-Sariha in al-Jazira state... which led to more than 200 injured and 124 martyrs," Health Minister Haitham Mohamed Ibrahim said.

The UN Children's fund (UNICEF) said at least 10 children were among those killed in al-Jazira over the past week.

The war in Sudan has killed tens of thousands of people, with some estimates of 150,000 dead.

Late Friday, activists from a local resistance committee had said the RSF attack on al-Sariha village had killed 50 and wounded more than 200.

But the committee, one of hundreds of volunteer groups coordinating aid in Sudan, reported a total "inability to evacuate the wounded from the village due to the shelling and snipers" from the RSF.

Ibrahim said his ministry was working "to urgently supply medicine and take care of the injured and sick in the besieged zones."

On October 20 the army announced that the RSF's al-Jazira commander Abu Aqla Kaykal had abandoned the paramilitaries, bringing "a large number of his forces" with him, in what it said was the first high-profile defection to its side.

Activists accused the paramilitaries of carrying out "vengeful operations against defenceless" civilians in response to Kaykal's defection.

They reported at least 20 people killed in subsequent paramilitary attacks in eastern al-Jazira. They also said an air strike by the Sudanese Armed Forces on a mosque in the state capital, Wad Madani, killed 31 people.

World's worst

Sudan's war has caused what the UN calls the world's largest displacement crisis, with more than seven million uprooted.

In June, Linda Thomas-Greenfield, the United States ambassador to the UN, said Sudan is also the planet's "largest humanitarian crisis".

Earlier on Monday, United Nations Secretary-General Antonio Guterres told the Security Council that Sudan's "suffering is growing by the day."

He said he was horrified by reported attacks against civilians being committed by both sides.

"The people of Sudan are living through a nightmare of violence -- with thousands of civilians killed, and countless others facing unspeakable atrocities, including widespread rape and sexual assaults."

Despite this suffering, Guterres said that at present "the conditions do not exist for the successful deployment of a United Nations force to protect civilians in Sudan."

Famine was declared in July in the Zamzam camp for displaced people near the town of El-Fasher, in Sudan's western Darfur region bordering Chad.

World Food Programme director Cindy McCain on Sunday told AFP that the rest of Sudan is at famine alert level, making it urgent that her agency get "complete and unfettered access."