More than 60,000 people have fled the Sudanese city of el-Fasher, which was captured by the paramilitary Rapid Support Forces (RSF) over the weekend, according to the UN refugee agency.

Reports have surfaced of mass executions and crimes against humanity as RSF fighters stormed the city after an 18-month siege marked by starvation and heavy bombardment.

The influx of individuals fleeing the violence towards the town of Tawila, located about 80km (50 miles) west of el-Fasher, has accelerated in recent days, as confirmed by UNHCR's Eujin Byun. Survivors have recounted horrific atrocities, including incidents of rape, and the agency is struggling to provide adequate shelter and food.

Every child among the displaced is reported to be suffering from malnutrition. An estimated 150,000 people remain trapped in el-Fasher, which had been the last stronghold of the army in the western region of Darfur.

The RSF has denied allegations of widespread ethnic targeting, claiming that the killings are not motivated by ethnicity.

In response to the accusations, the RSF detained one of its militiamen, Abu Lulu, who allegedly was involved in summary executions. Footage of his arrest was released after he was identified by BBC Verify as being responsible for multiple killings near el-Fasher.

The ongoing conflict, which erupted into civil war in April 2023, has led to widespread famine and claims of genocide in Darfur, with over 150,000 deaths reported and around 12 million people displaced, marking it as the world's largest humanitarian crisis.

The RSF's control over el-Fasher signifies a geographical split in Sudan, with RSF dominating the western regions and the army maintaining control over central areas and the capital, Khartoum. Previously, the two factions had acted as allies before their rupture amidst a failed move towards civilian governance.