Scores of people have been killed in attacks by the Rapid Support Forces (RSF) during their recent capture of the city of el-Fasher in Sudan’s western Darfur region, according to a medical group and researchers.

The RSF, which has been fighting Sudan’s military for control of the country, killed at least 1,500 people over the past three days as civilians tried to flee the besieged city, the Sudan Doctors Network said on Wednesday. The group, which tracks the country’s civil war, described the situation as “a true genocide”.

“The massacres the world is witnessing today are an extension of what occurred in el-Fasher more than a year and a half ago, when over 14,000 civilians were killed through bombing, starvation, and extrajudicial executions,” the group said.

It said the attacks are being carried out as part of a “deliberate and systematic campaign of killing and extermination”.

The statement comes as new evidence of mass killings in the strategic area has emerged from Yale’s Humanitarian Research Lab (HRL), which reported that satellite imagery of el-Fasher, taken after the RSF moved in, shows clusters of objects consistent with the size of human bodies, as well as large areas of red discolouration on the ground.

The RSF has been locked in a bloody civil war with Sudan’s army since 2023, in a conflict that has killed tens of thousands and displaced more than 12 million people.

The paramilitary force overran el-Fasher, the army’s last stronghold in Darfur, on Sunday after 17 months of siege.

The Sudanese government said on Wednesday that at least 2,000 people have been killed in the city since then, while aid agencies say they have received credible reports of atrocities, including summary executions, attacks on civilians along escape routes, and house-to-house raids.

Sexual violence, particularly against women and girls, was also reported in the city, they said.

El-Fasher’s fall puts the RSF in near full control of the vast region of Darfur and has raised concerns of another split of Sudan, more than a decade after South Sudan’s creation.

“More than 2,000 civilians were killed during the militia’s invasion of el-Fasher, targeting volunteers in mosques and the Red Crescent,” Mona Nour Al-Daem, a humanitarian aid officer for the Sudanese government, said.

Al Jazeera’s Hiba Morgan, reporting from Khartoum, said videos on social media taken by the RSF showed fighters “shooting at civilians attempting to flee”.

“The latest and most disturbing video to surface was of the fighters roaming through what has been identified as the Saudi Hospital in the city of el-Fasher, executing patients,” Morgan said.

Survivors who fled the city said at least 500 people had been seeking refuge in the hospital.

Among those killed were health workers, Morgan added.

Tedros Adhanom Ghebreyesus, director general of the World Health Organization (WHO), said that more than 460 people were killed at the Saudi Maternity Hospital.

He said the WHO was “appalled and deeply shocked” by the reports.

The Sudan Doctors Network said RSF fighters on Tuesday “cold-bloodedly killed everyone they found inside the Saudi Hospital, including patients, their companions, and anyone else present in the wards”.

Saudi Arabia expressed “deep concern” over grave human rights violations and urged the RSF to protect civilians. Egypt called for an immediate humanitarian truce and pledged continued support to help Sudan overcome the crisis.

Turkiye demanded an end to hostilities in el-Fasher and safe passage for humanitarian aid, while condemning “atrocities against civilians” and urging dialogue for a peaceful solution. Qatar also denounced the “horrific violations” and called for negotiations to end the conflict.

Egypt, Turkiye and Qatar reaffirmed their support for Sudan’s unity and sovereignty. Jordan likewise condemned the violence and called for restraint and an urgent ceasefire to protect civilians.

Separately on Tuesday, Yale’s HRL published a report relying on satellite imagery that said that RSF forces were “conducting alleged mass killings” after seizing el-Fasher.

Nathaniel Raymond, HRL’s executive director, described the violence in el-Fasher as unprecedented.

“The scale is immense, from the earthen berm, the wall that now surrounds el-Fasher, to specific neighbourhoods, such as Daraja Oula, to hospitals and humanitarian facilities. We are seeing objects that measure between 1.5 to 2 metres [5 to 6.5 feet], which is the standard length of a human body, lying horizontal, as seen in satellite imagery at high resolution,” he told Al Jazeera.

“Those objects were not there 36 to 48 hours ago. They now litter the city.”

The researcher warned that the killings were a preview of what could happen in other areas of Darfur and the North Kordofan province as RSF forces move to the east of the country with the fall of el-Fasher.

Ahmed Ibrahim, a former staffer of the transitional government under Sudanese Prime Minister Abdalla Hamdok, said the RSF was meant to be integrated into the national army, but due to “geopolitical” reasons and “internal politics”, this did not happen.

“Many bets were on the RSF militia to take over the resources of the country and replace the national army and take over the whole country,” Ibrahim told Al Jazeera.

The timeline of this integration, and the RSF’s new leadership, were the main “points of contention that led to this war”, he said.

According to Ibrahim, the war has been taking place as Sudan’s “rare earth minerals and long [Red] sea line” were being utilised to export livestock and other resources to East African countries as an attempt to “strip Sudan of its national resources”.

“This is not just a power struggle between two generals,” Ibrahim said. “This is part of a geopolitical attempt to restructure the region.” (Al Jazeera, but headline rejigged)

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