Doctors in the Sudanese capital were beaten and whipped by gunmen who attacked their convoy, medical charity Médecins Sans Frontières (MSF) said.
A medical team was transporting supplies to the Turkish hospital south of Khartoum when it came under attack on Thursday and one of their vehicles was stolen.
Since war broke out in mid-April, it has been one of only two hospitals still operating in the south of the city.
Both are supported by MSF, which says its aid is now under threat.
The fierce power struggle of the past three months between the army and the paramilitary Rapid Support Forces (RSF) has devastated the city’s medical facilities.
‘Death threats’
While more than three million people across the country have fled their homes since April, millions more are still stuck in Khartoum, struggling to find medicine and medical assistance.
MSF is one of the few international aid groups still supporting hospitals in Khartoum and its twin city of Omdurman, helping to keep a decades-old health system afloat.
She claims to have treated more than 1,600 patients in these hospitals since the beginning of the conflict.
But the charity warned that this may have to come to a halt due to a dramatic deterioration in security with several incidents in which its staff had been targeted.
During Thursday’s clash, the armed men began to argue with the 18-person MSF convoy of four trucks carrying medical equipment.
In addition to attacking the team, the armed men threatened to kill one of the drivers before releasing him and fleeing with one of the vehicles.
“If an incident like this happens again and our ability to get supplies continues to be hampered, then, unfortunately, our presence in the Turkish hospital will soon become unsustainable,” MSF’s Christophe Garnier said in a statement.
The confrontation took place not far from the hospital, where hundreds of patients, including those recently injured in airstrikes, are being treated.
“On a daily basis, this hospital receives around 15 war-wounded, performs vital surgeries and keeps patients suffering from chronic illnesses alive,” MSF said.
According to the AFP news agency, the hospital is in an area of the city controlled by the RSF.
Aerial bombardment has intensified in residential areas of Khartoum where paramilitary fighters have their bases, he said.
Official figures put the death toll in the conflict at around 3,000, but it is thought to be much higher.
Some estimates from the western Darfur region, which has seen the worst of the violence, put the death toll in one town alone at 11,000.