The UN Security Council has announced new sanctions on four leaders of Sudan's paramilitary Rapid Support Forces over atrocities committed in the western Sudanese city of el-Fasher.

The deputy commander, Abdul Rahim Hamdan Dagalo and Brigadier General Al-Fateh Abdullah Idris, more commonly called Abu Lulu, who became known as the "Butcher of el-Fasher", are among those proscribed.

The others are RSF deputy commander Gedo Hamdan Ahmed and field commander Tijani Ibrahim.

A spokesman for Tasis, a coalition of civilian and armed groups led by the RSF, told the BBC the sanctions were "unfair", saying they were based on what he described as "partial" and "unneutral" reports.

The RSF's capture of the city in October was one of the most brutal chapters of Sudan's nearly three-year civil war.

Last week a UN fact-finding mission concluded that the violent takeover bore the hallmarks of a genocide.

The RSF has admitted that "violations" were committed in el-Fasher and says it is investigating them, but insists the scale of the atrocities has been exaggerated by its enemies.

In a response to the BBC, Tasis termed the accusations of killing civilians and preventing them from leaving el-Fasher "misleading". It said its forces had evacuated more than 800,000 civilians from el-Fasher during the military operations there, and "provided them with food and medicine".

"All these facts showed that the sanctions imposed by UNSC are unjust," it added.

The UN said Dagalo, brother of RSF chief Mohamed Hamdan Daglo, known as "Hemedti", had overseen operations on the day the RSF captured el-Fasher, citing atrocities carried out by his forces including mass killings and ethnically targeted executions.

This is the fourth time Dagalo has been sanctioned – following earlier designations by the United States, the United Kingdom and the European Union.

The Sentry group, an investigative American non-profit organization which seeks to disable networks that benefit from violent conflicts - has said it is encouraging to see alignment in targeting officials, but far more is needed to impose real financial consequences on the RSF and the networks that sustain it.

Sudan has been engulfed in conflict since April 2023, as fighting between the RSF and the army has escalated into what the UN describes as a "war of atrocities", leaving tens of thousands dead and triggering the world's worst hunger and displacement crisis.

For 18 months, the RSF besieged el-Fasher - the capital of North Darfur and the last major city they did not control in the western region of Darfur - before taking the city on 26 October.

The UN fact-finding mission described the campaign as "three days of horror", marked by summary executions, systematic sexual violence and mass detention, primarily targeting the city's ethnic Zaghawa population.

Abu Lulu became known as "the Butcher of el-Fasher" for graphic videos he himself posted of the takeover.

He appears in footage "giving orders to his men to kill innocent people'', the UN said. It added that video footage shows him executing civilians and boasting about killing over 2,000 people.

Tasis said Abu Lulu had already been imprisoned by its forces. The group said this demonstrated that they did not tolerate abuses against civilians, adding that what had occurred were "individual incidents", not official doctrine.

The US imposed sanctions on Dagalo in September 2023 and on the three other commanders last week, over their roles in the "ethnic killings, torture, starvation and sexual violence" committed in el-Fasher.

Britain sanctioned all four in December.

The UN did not specify what its designations involved but it has the powers to order measures such as an assets freeze and a travel ban.

More than 70,000 people have fled el-Fasher since it was captured, with civilians remaining trapped or missing, or being held by the RSF inside the city, according to the UN's refugee agency.