DUBAI, United Arab Emirates >> About 70 people were killed in an attack on the only functional hospital in the besieged city of El Fasher in Sudan, the chief of the World Health Organization said Sunday, part of a series of attacks coming as the African nation’s civil war escalated in recent days.

The attack on the Saudi Teaching Maternal Hospital, which local officials blamed on the rebel Rapid Support Forces, came as the group was experiencing apparent battlefield losses to the Sudanese military and allied forces under the command of army chief Gen. Abdel-Fattah Burhan. That includes Burhan appearing near a burning oil refinery north of Khartoum on Saturday that his forces said they seized from the RSF.

Saudi Arabia’s Foreign Ministry denounced the attack as “a violation of international law.”

International mediation attempts and pressure tactics, including a U.S. assessment that the RSF and its proxies are committing genocide, and sanctions targeting Burhan, haven’t halted the fighting.

WHO Director-General Tedros Adhanom Ghebreyesus posted the death toll in the hospital attack in El Fasher on the social media platform X.

Officials and others in the capital of North Darfur province had cited a similar figure Saturday, but Tedros is the first international source to provide a casualty number. Reporting on Sudan is incredibly difficult given communication challenges, the indiscriminate violence faced by civilians and exaggerations by both the RSF and the Sudanese military.

“The appalling attack on Saudi Hospital in El Fasher, Sudan, led to 19 injuries and 70 deaths among patients and companions,” Tedros wrote. “At the time of the attack, the hospital was packed with patients receiving care.”

Another health facility in Al Malha also was attacked Saturday, he said.

“We continue to call for a cessation of all attacks on health care in Sudan, and to allow full access for the swift restoration of the facilities that have been damaged,” Tedros said. “Above all, Sudan’s people need peace. The best medicine is peace.”

Tedros didn’t identify who launched the attack, though local officials had blamed the RSF for the assault. Sudan’s Foreign Ministry also accused the RSF of launching a drone attack targeting the hospital’s emergency ward, describing the assault as a “massacre.”

U.N. official Clementine Nkweta-Salami, who coordinates humanitarian efforts for the world body in Sudan, warned Thursday that the RSF earlier had given “a 48-hour ultimatum to forces allied to the Sudanese Armed Forces to vacate the city and indicated a forthcoming offensive.”

In a statement Sunday night, the RSF alleged that the Sudanese military and its allies attacked the hospital in El Fasher, but offered no evidence to support the claim. El Fasher is more than 500 miles southwest of Khartoum.