Hassan Koko sits on top of a homemade wooden bed, overlooking the majestic hills of the Nuba Mountains in South Kordofan, Sudan.

Despite the spectacular view and a comforting late afternoon breeze, he looks uneasy.

On November 29, the 50-year-old community health worker had finished a training course and was enjoying some sweet tea when a drone suddenly appeared. When it landed, it killed a number of Koko's colleagues.

"The drone struck once, then came back again, hitting those who were already wounded," he tells DW.

While Koko himself survived, the attack left a heavy mark on him. Quite physically so. He points to his left knee. Inside it, remains a sharp metal object, now three months after the attack, clearly visible. 

"My family was happy I survived. They thought I would die," he says. "But life is not the same anymore. Sometimes, I walk down to the nearby market, but mostly, I'm just stuck at home."

A shifting alliance

For decades, the people of the Nuba Mountains, controlled by the armed Sudan People's Liberation Movement-North (SPLM-N), have grown accustomed to attacks from Sudan's Armed Forces (SAF). 

The current conflict dates back to 2011, when fighting intensified after the area around the Nuba Mountains was excluded from the political settlement, which resulted in South Sudan's independence. It deepened the long-standing grievances for the Nuba populations, a loose definition of the more than 50 ethnic groups inhabiting a territory the size of Austria.

The SPLM-N, emerging from the SPLA liberation movement that now constitutes South Sudan's military, was founded that same year to represent the Nuba populations' demand for self-rule. 

However, it was not until February 2025 that a significant shift occurred when the SPLM-N, faced with growing hostilities, decided to join forces with the paramilitary Rapid Support Forces (RSF). 

This was seen by most as a precarious, highly controversial alliance. 

The ongoing Sudan warbegan in 2023 and has triggered the world's most severe humanitarian crisis. According to several estimates, it has resulted in more than 150,000 deaths and caused the forced displacement of some 14 million civilians. 

Jalale Getachew Birru, a senior analyst at the Armed Conflict Location & Event Data (ACLED) project, argues that the alliance must be understood as a pragmatic response and perceived in the light of the RSF and SPLM-N's shared desire for a future federal system in Sudan. 

"Both sides have a common interest, and that's why they are aligned at this moment, to push back against the SAF," she says. 

Overwhelmed by war refugees

In the Nuba Mountains' urban centres, RSF soldiers are casually roaming, chatting at cafes and hanging around populated markets, selling recently looted items from across Sudan: cars, beds, fuel, fertilizers, electronic devices and much more.

However, RSF soldiers are not the only newcomers here. 

At an office in Kauda village, the SPLM-N headquarters, Jalal Abdulkarim sits stiffly behind his desk. Abdulkarim represents the movement's humanitarian efforts, coordinating support for refugees in so-called liberated areas. 

He does not hide the pressure that the SPLM-N is currently facing. Abdulkarim hands over a note: "2,885,393" is written on the yellow slip of paper — the number of refugees received in SPLM-N-controlled areas since the beginning of the Sudan war. 

Funding for refugee programs largely depends on external NGOs and UN agencies, Abdulkarim says, but they, too, are under financial strain. Following Donald Trump's dismantling of the US Agency for International Development (USAID) last year, funding has fallen short of providing the food, water, shelter and sanitation needed for the many new arrivals. 

"If an NGO previously donated $1or $2 million [€848,000 or €1.7 million], today it's just $500,000 or $200,000. This is one of the biggest challenges we face," said the SPLM-N bureaucrat. 

The International Organisation for Migration (IOM) estimates that Kordofan hosts "more than a million" internally displaced persons. However, as no apparent UN presence remains in the capital of South Kordofan State, Kadugli, and most international NGOs have suspended or significantly reduced their operations in the region, these figures may be subject to inaccuracies.

Temporary shelter in the Nuba Mountains

Deeper into the rugged terrain of the Nuba Mountains lies the Umm Dulo Reception Camp, a barren expanse where internally displaced people have erected temporary shelters from sticks and plastic, often beneath the shadows of large acacia trees. 

In Zone 12, at the far end of the camp of more than 34,000 people, the newest arrivals are housed. Fatma Eisa Kuku, a 76-year-old, recalls the life she fled in Kadugli. 

"I couldn't sleep. Every night was rat-tat-tat-tat," she says, mimicking the sound of gunfire.

In the Umm Dulo camp, Kuku has found temporary shelter and recently returned to peaceful sleep. Yet she cannot forget the sudden abduction of three men in particular. 

"They came between dawn and dusk, and I haven't seen my brothers since," she says. "I don't know who these people were. If you ask about their identities, you'll be faced with a lot of rudeness." 

New guests kept at arm's length

Although the people of the Nuba Mountains do not explicitly state it, the tension is pervasive. The RSF rarely blends in with the local communities. It's like adding a new, unfamiliar layer to years of inherited anxiety. 

Moreover, the presence of SPLM-N's new ally around hospitals and markets has turned these crowded spaces into potential war targets. It's a predicament only too familiar to the Nuba peoples.

According to Jalale Getachew Birru, little is known about the military agreement between RSF and the SPLM-N, although the senior analyst cites credible reports that the RSF has established military training camps within SPLM-N-controlled territories. 

Generally, however, Jalale Getachew Birru is not convinced about the alliance's longevity. When the SAF broke the siege of Kadugli earlier this year, long-controlled by the SPLM-N and RSF, the allies even started blaming each other for the loss, she explains. 

"There was a clash where we were keeping an eye to see whether it was a sign for this alliance to finally break, and for them to go separate ways," she says. 

At this point in time, however, the alliance holds.

'I want to live in the Nuba Mountains forever'

At the Mother of Mercy Hospital, the biggest hospital in the SPLM-N-controlled areas, three young, wounded RSF soldiers have dragged their beds outside and into the shadows to escape the afternoon heat.

After horrific reports of systematic killings and vicious war crimes, the RSF has been described as one of the most relentless militias of our time. But what, in their own words, are the soldiers actually fighting for?  

"We are fighting because the government [in Sudan] is not doing enough. There are not enough hospitals, infrastructure and schools," Hassan Hamid explains.

For now, the RSF fighter has found unexpected refuge in the Nuba Mountains, and there's no indication that he and his comrades are leaving anytime soon. "I want to stay here," he says. "I want to live in the Nuba Mountains forever." 

Edited by: Benita van Eyssen