Research Breakdown: Sudan’s Blood Visible from Space

Research Organization

Yale Humanitarian Research Lab (HRL) at Yale School of Public Health

Led by Nathaniel Raymond, Executive Director
Uses satellite imagery analysis combined with open-source intelligence (OSINT)
Primary satellite imagery providers: Airbus Defence and Space, Vantor

Report Links:

What Happened: The Fall of El-Fasher

Location: El-Fasher, capital of North Darfur, western Sudan

Timeline:

18-month siege by Rapid Support Forces (RSF) beginning around April 2024
October 26-27, 2025: RSF captured the city after the Sudanese Armed Forces (SAF) withdrew
First 72 hours: Mass killings documented through satellite imagery
Population trapped: ~250,000-260,000 civilians besieged; only ~65,000 escaped

Key Findings from Satellite Analysis

Visual Evidence Detected from Space:

Reddish-brown ground discoloration consistent with blood-soaked soil

Multiple patches large enough to be visible from satellite imagery
Discoloration not present in previous satellite images taken before October 26

Clusters of white objects measuring 1.3-2.0 meters

Consistent with human bodies lying horizontally
Found across multiple locations throughout the city

Locations where bodies/blood were detected:

Residential neighborhoods (especially Daraja Oula district)
Saudi Hospital grounds (last functioning hospital)
Former Children’s Hospital (RSF detention center)
Red Crescent Society offices
Military bases (6th Division HQ, 157th Artillery Brigade)
Along the earthen wall (berm) surrounding the city
University grounds and medical science laboratory

Tactical Patterns Observed:

RSF military vehicles (technicals - gun-mounted trucks) consistently positioned near body clusters, indicating:

Systematic house-to-house clearance operations
Controlled movement and execution sites
Deliberate positioning for mass killings

Evidence of fleeing civilians being targeted:

28 destroyed vehicles along escape routes
Body clusters along roads and near the defensive berm
Objects resembling bodies near vehicles attempting to flee

Methodology

Data Fusion Approach:

High-resolution satellite imagery analysis
Open-source intelligence (social media, local reports)
Video verification from multiple sources
Witness testimony correlation
Temporal analysis (comparing imagery across days)

Limitations acknowledged by researchers:

Limited data availability in Sudan conflict zones
Reporting bias from those able to communicate
Difficulty assessing detention, sexual violence without ground access
Satellite imagery limited by available coverage and angles

Scale of Violence

Estimated casualties:

Yale HRL: Described as comparable to 1994 Rwanda genocide in velocity
Local defense groups: Over 2,000 civilians killed in first 48 hours
Sudan War Monitor: Estimated 3,000+ deaths by October 30
Researchers: Likely tens of thousands killed in the first week
WHO: 460+ executions at Saudi Hospital alone

Nathaniel Raymond’s assessment:

“We have never seen a velocity of violence at this scale… The level of violence and number of incidents in Darfur exceed anything I have seen so far.”

Patterns of Atrocities Documented

Gender-based targeting:

Men separated from women and children
Reports of men being executed after separation
Women and children raped while fleeing

Medical facility attacks:

Saudi Hospital: Mass executions of wounded patients and staff
Red Crescent offices stormed, medics forced into combat vehicles
All hospitals rendered non-functional

Systematic ethnic cleansing:

Targeting of Fur, Zaghawa, and Berti ethnic groups
House-to-house clearances in specific neighborhoods
Racial epithets used in RSF videos of killings

Prevented escape:

57-kilometer berm wall entrapping population
Checkpoints where fleeing civilians were killed
Communications blackout preventing information flow

Historical Context

RSF Origins:

Descended from Janjaweed militias responsible for 2003-2005 Darfur genocide
Previously called “devils on horseback” for rape and murder campaigns
Now use trucks, drones, and modern weapons instead of horses

Current Conflict:

Sudan civil war began April 2023
Power struggle between SAF leader General Abdel Fattah al-Burhan and RSF commander Mohamed Hamdan Dagalo (“Hemedti”)
12+ million displaced, considered world’s worst humanitarian crisis
30 million need emergency aid

US Determination:

January 2025: US State Department determined RSF committed genocide in Darfur

International Response

Geopolitical Backing:

United Arab Emirates (UAE) supplies RSF with weapons, drones, funds, and mercenaries
British-manufactured arms components recovered from RSF combat zones
IL-76 cargo aircraft (linked to UAE resupply) documented near El-Fasher

International Statements:

Tom Fletcher (UN Under-Secretary-General): “Blood on the sand… Blood on [our] hands”
German Foreign Minister: Called it “absolutely an apocalyptic situation, the greatest humanitarian crisis of the world”
Peace talks sponsored by US stalled when UAE refused to address El-Fasher situation

Legal Framework: Yale HRL assessment: Actions may constitute war crimes, crimes against humanity, and genocide

Current Situation (as of early November 2025)

RSF controls all five Darfur state capitals
Sudan effectively split east-west
Most El-Fasher civilians remain “dead, captured, or in hiding”
No large-scale movement of survivors detected
Mass killings continuing through early November
Communications blackout prevents accurate casualty counts

Comparative Historical Analysis

Raymond compared the velocity and systematic nature to:

Rwanda 1994: ~800,000 killed by ethnic militias
Current situation: Potentially exceeding Rwanda’s pace in affected areas

Sources & Further Reading

Note: This research represents one of the first documented instances where pools of human blood from mass killings were extensive enough to be detected and analyzed via commercial satellite imagery, marking a disturbing milestone in both conflict documentation and the scale of atrocities.

Research indicates Sudan genocide visible from space