Sudan’s paramilitary forces have reportedly committed a tragic massacre at a hospital, killing hundreds, including patients, after taking control of North Darfur’s provincial capital over the weekend. This grim news comes from the U.N., displaced residents, and aid workers who have shared disturbing accounts of the violence.

According to Tedros Adhanom Ghebreyesus, the World Health Organization’s director-general, fighters from the Rapid Support Forces (RSF) are said to have killed 460 patients and their companions on Tuesday at Saudi Hospital in el-Fasher.

Witnesses recounted to The Associated Press that, while attacking el-Fasher, RSF combatants went door-to-door, assaulting and shooting residents, including women and children. Many victims were shot in the streets, some tragically caught in the crossfire while attempting to escape.

The ongoing conflict for control of Sudan, now in its second year, has resulted in over 40,000 deaths—though rights groups believe this number is a significant underestimate—and has sparked the world’s most severe humanitarian crisis, displacing over 14 million people. With the RSF now controlling el-Fasher, there are growing concerns that Africa’s third-largest country might face division again, years after South Sudan’s secession following a prolonged civil war.

Sudanese locals and aid workers have provided chilling accounts of the RSF’s actions after capturing the army’s final stronghold in Darfur, following a siege lasting more than 500 days.

The Sudan Doctors Network, an organization monitoring the conflict, reported that RSF fighters “cold-bloodedly killed everyone they encountered inside Saudi Hospital, including patients, their companions, and all present in the wards.”

“The Janjaweed showed no mercy for anyone,” said Umm Amena, a mother of four children who fled the city on Monday after two days, using a Sudanese term for the RSF.

RSF commander Gen. Mohammed Hamdan Dagalo, who is sanctioned by the U.S., acknowledged what he called “abuses” by his forces. In his first comments since the fall of el-Fasher, posted Wednesday on the Telegram messaging app, he said an investigation was opened. He did not elaborate.

The Associated Press has not been able to independently confirm the hospital attack and death toll.

‘It was a like a killing field’

Mini Minawi, the governor of Darfur, shared a video online that purported to show RSF fighters inside the Saudi Hospital. The minute-long footage shows bodies lying on the floor in pools of blood. A fighter fires a single shot from a Kalashnikov-style rifle into a lone man sitting up, who then slumps to the floor. Other bodies could be seen outside. The AP could not independently verify the date, location or condition under which the video was recorded.

Amena was among three dozen people, mostly women and children, who were detained for a day by RSF fighters in an abandoned house close to the Saudi Hospital in el-Fasher.

The AP spoke with Amena and four others who managed to flee el-Fasher and arrived exhausted and dehydrated early Tuesday in the nearby town of Tawila, around 60 kilometers (37 miles) west of el-Fasher, which already hosts over 650,000 displaced.

The U.N. migration agency said more than 36,000 people have fled el-Fasher, mostly to rural areas around it, since Sunday.

U.N. refugee agency official Jacqueline Wilma Parlevliet said the new arrivals told of widespread killings motivated by ethnic and political differences, including reports of people with disabilities shot dead because they were unable to flee, and others shot as they tried to escape.

“It was a like a killing field,” Tajal-Rahman, a man in his late 50s, said over the phone from the outskirts of Tawila. “Bodies everywhere and people bleeding and no one to help them.”

Both Amena and Tajal-Rahman said RSF fighters tortured and beat the detainees and shot at least four people Monday who later died of wounds. They also sexually assaulted women and girls, they said.

In Tawila, a hospital run by Doctors Without Borders received many patients since Oct. 18 suffering from injuries related to bombings or gunshots, according to Giulia Chiopris, a pediatrician at the hospital.

She said the hospital also received a high number of malnourished and severely dehydrated children, many of them unaccompanied or orphaned, who had fled el-Fasher.

“We are seeing a lot a lot of cases of trauma related to the last bombing and a huge number of orphans,” she said.

She recalled receiving three young siblings, ranging in age from 40 days old to 4 years, whose family was killed in the city. They were brought to the hospital Monday night by strangers, she said.

Satellite imagery suggest mass killings

In a report late Tuesday, the Yale School of Public Health’s Humanitarian Research Lab said that RSF fighters continued to carry out mass killings since they took over el-Fasher.

The report, which relied on satellite imagery from Airbus, said it corroborated alleged executions and mass killing by the RSF around the Saudi Hospital, and at a detention center at the former Children’s Hospital in the eastern part of the city. The AP accessed and analyzed the same imagery, seeing objects and red stains on the ground at the sites that the lab identified as blood and bodies.

The lab also said that “systematic killings” took place in the vicinity of the eastern wall, which the RSF built outside the city earlier this year.

Sheldon Yett, the UNICEF representative to Sudan, said in an interview that the situation in el-Fasher, was “an absolute catastrophe,” with thousands of children already suffering from disease and famine before the takeover of the city by the RSF.

“Now it’s hell on Earth with lots of guns,” Yett said.

Aid groups said a death toll has been difficult to determine since RSF overran el-Fasher, given a near communication blackout.

The report from Yale said satellite imagery can’t show the true scale of the mass killings, and that an estimated death toll is likely an undercount.

Before the latest bout of violence, some 1,850 civilians were killed in North Darfur, including 1,350 in el-Fasher, between Jan. 1 and Oct. 20 this year, according to U.N. spokesperson Farhan Aziz Haq.

Global outrage

Footage of the attacks triggered a wave of outrage around the world. France, Germany, the United Kingdom and the European Union all condemned the atrocities.

Mohamed Osman, Sudan researcher with Human Rights Watch, said that footage coming out of el-Fasher “reveals a horrifying truth: the Rapid Support Forces feel free to carry out mass atrocities with little fear of consequences.”

“The world needs to act to protect civilians from more heinous crimes,” he said.

Massad Boulos, the U.S. senior adviser on Arab and African affairs, condemned the attacks.

“The deliberate targeting of vulnerable populations through acts of violence and retribution is both abhorrent and unacceptable,” wrote Boulos, a Lebanese-American businessman who is the father-in-law of President Donald Trump’s daughter Tiffany.

“We acknowledge RSF leadership’s recent statements on civilian protection, humanitarian access and accountability, but words alone will not save lives. These commitments must urgently be turned into concrete actions on the ground to alleviate the suffering of the Sudanese people.”

Sen. Jim Risch, chairman of the U.S. Senate Foreign Relations Committee, on Tuesday denounced the RSF attacks on the city, and called for it to be designated as a foreign terrorist organization. “The RSF has waged terror and committed unspeakable atrocities, genocide among them, against the Sudanese people,” he wrote.