UNITED NATIONS - Local sources reported more than 300 civilians were killed in attacks on Sudan's famine-distressed Zamzam displacement camp, UN humanitarians said on Monday.

The Office for the Coordination of Humanitarian Affairs (OCHA) said it is gravely concerned by reports of mass casualties and large-scale displacement following intense fighting on Friday and Saturday in and around Zamzam and Abu Shouk displacement camps and the town of El Fasher in North Darfur.

"Preliminary figures from local sources indicate that more than 300 civilians have been killed, including 10 humanitarian personnel from the NGO Relief International who lost their lives while operating one of the last functioning health centers in Zamzam camp," OCHA said.

The UN Children's Fund (UNICEF) said at least 23 children were killed in the attacks.

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UN Secretary-General Antonio Guterres condemned the killings, said his spokesman Stephane Dujarric on Monday.

"Our Humanitarian and Resident Coordinator in Sudan, Clementine Nkweta-Salami, also condemned the violence in the strongest terms and called for an immediate end to the hostilities and the protection of civilians and humanitarian workers," said Dujarric. "The perpetrators of these attacks must be brought to justice."

The sprawling Zamzam camp is about 15 km south of El Fasher, North Darfur state's capital and economic hub. Abu Shouk camp is on the edge of the city. In February, the United Nations said famine existed in Zamzam and Abu Shouk camps.

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The International Organization for Migration (IOM) said at least 16,000 people were displaced from the Zamzam camp, with many fleeing to El Fasher and, to the west, Tawila.

However, OCHA said local partners reported that the humanitarian and security situation in El Fasher is rapidly deteriorating due to continued violence and a growing influx of displaced people.

IOM said that east of El Fasher in the town of Um Kadadah in North Darfur, local sources reported more than 50 people killed and 900 homes destroyed in recent fighting. The agency estimated that about 19,000 people had been displaced from the area since Thursday.

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OCHA said residents and displaced people in Zamzam and El Fasher face severe shortages of essential supplies, including food, fuel and health items. Diesel fuel prices surged fivefold in the past three months, significantly limiting access to safe drinking water and forcing the suspension of some water trucking services.

OCHA said some relief supplies were pre-positioned in nearby locations such as Tawila and Al Kuma. Humanitarian partners mobilized additional relief items, including 1,800 metric tons of food assistance, to Tawila to help meet the urgent needs of displaced families.

The World Health Organization said there have been about 160 attacks on healthcare since the onset of the conflict two years ago, resulting in more than 300 deaths. One-third of hospitals are non-functional, and recent funding cuts forced health partners to scale down support to more than 300 health facilities nationwide.

Civil war erupted in Sudan on April 15, 2023, with attacks by the Rapid Support Forces militia on the capital of Khartoum.