A newly released United Nations investigation has traced a covert pipeline moving foreign fighters and military supplies from southern Libya into Sudan’s war, linking Colombian ex-soldiers to the Rapid Support Forces as the conflict enters its fourth year.

According to the report, an armed Libyan faction played a central role in ferrying recruits, fuel and weapons across borders to bolster the RSF in its battle against Sudan’s army. The findings surfaced just days after the third anniversary of the war.

Libya’s Subul al-Salam Battalion emerges as the key player in the network, with investigators saying it organised the transfer of fighters, including Colombian mercenaries, and handled the flow of logistics into RSF-controlled territory.

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The battalion operates under the self-styled Libyan National Army led by Gen. Khalifa Hifter, which controls large swathes of eastern and southern Libya. Its footprint is strongest in Kufra, a desert town near the borders with Sudan, Chad and Egypt. There, it oversees key infrastructure, including an airstrip believed to have been used to move fighters and weapons into Sudan.

The U.N. Panel of Experts on Libya compiled the report, covering the period from October 2024 to February 2026, and released it on Sunday.

Sudan’s war erupted on April 15, 2023, when tensions between the national military and the RSF spiralled into open combat in Khartoum before spreading nationwide.

Investigators outlined how Libya served as a strategic rear base for the RSF, including a site roughly 75 kilometres southwest of Kufra. The paramilitary group also relied on facilities in Kufra as transit hubs for Colombian fighters and as locations where imported vehicles were modified for combat use.

The report says the Libyan battalion deepened its involvement in June 2025, deploying fighters on the ground while ensuring supply lines remained intact. It described how the group moved personnel through Libyan territory and kept them operational with fuel and spare parts, stating it was “escorting them across Libyan territory and facilitating access to fuel and spare vehicle parts.”

That support proved significant in RSF advances toward the Uwaynat triangle, where Sudan, Egypt and Libya converge, although the report notes it came at the cost of eroding border security in southern Libya.

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The AP indicated in a report that, neither the RSF nor the Subul al-Salam Battalion responded to requests for comment.

The RSF claimed in June that it had taken control of the border triangle after Sudan’s military said it withdrew under what it called “its defensive arrangements to repel aggression.” Military officials in Khartoum have accused Hifter’s forces of backing the RSF offensive, an allegation the Libyan commander has rejected.

Human rights groups have also pointed to the United Arab Emirates as a supporter of both Hifter’s forces and the RSF, an assertion the Gulf state continues to deny.

The report further details attempts by Sudan’s military to sever the Libya-based supply route. In November, it carried out airstrikes targeting convoys of vehicles and foreign fighters inside Libya believed to be heading toward RSF positions.

Meanwhile, the United States has sanctioned several Colombian entities and individuals accused of facilitating the deployment of former soldiers to fight alongside the RSF.

The war has pushed Sudan into famine and triggered what aid agencies describe as the world’s worst humanitarian crisis. At least 59,000 people have been killed, according to the Armed Conflict Location and Event Data Project, which warns the true figure is likely higher due to gaps in reporting.

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