The Doctors Without Borders (MSF) charity said Friday its team was attacked in Khartoum, warning it may suspend operations at one of the few hospitals still operating in war-torn Sudan's capital.
Armed men on Thursday beat 18 MSF employees and threatened one with death as they were transporting supplies to Khartoum's Turkish Hospital, the medical charity said in a statement.
The Turkish Hospital is one of only two medical facilities still open in southern Khartoum, MSF said.
It added both hospitals are in an area of the city controlled by the paramilitary Rapid Support Forces, which since April 15 have been fighting the regular army.
The war, led by feuding generals, has killed at least 3,000 people and displaced more than 3.3 million. Khartoum as well as the western region of Darfur have seen the worst of the violence.
After arguing about the reasons for their presence, the MSF team was "aggressively assaulted by a group of armed men, who physically beat and whipped them" while trying to reach the Turkish Hospital, the Geneva-based organisation said.
"They detained one of our drivers and threatened his life before releasing him. They also stole one of our vehicles."
The incident put their continued activities at the hospital in doubt, it added.
MSF says it is one of the few international medical humanitarian organizations still present in Khartoum.
The incident occurred about 700 metres (765 yards) from the Turkish Hospital, which on the same day, MSF said, received 44 patients wounded in an airstrike.
It said its activities in the hospital would not be able to continue without minimum safety guarantees.
"If an incident like this happens again, and if our ability to move supplies continues to be obstructed, then, regrettably, our presence in the Turkish Hospital will soon become untenable," said Christophe Garnier, MSF's emergencies manager for Sudan.
The fighting in Khartoum has intensified as warplanes pound residential areas to try to dislodge the RSF who set up bases there years ago.
Both sides also exchange regular artillery fire.
On Friday, more air raids shook several areas of Khartoum as well as the major city of El-Obeid 350 kilometres (220 miles) to the south, residents said.
The commercial hub is on the road connecting the capital to the vast western region of Darfur, a stronghold of the RSF that has also been gripped by deadly warfare.
El-Obeid airport is coveted by both sides in the conflict for its storage facilities of both aid supplies and gum Arabic, a major Sudan export, although these stocks are likely to have been looted.
MSF said it has treated more than 1,600 war wounded patients in Khartoum since the conflict began.
The World Health Organization has verified 51 attacks on healthcare in Sudan since the conflict began, resulting in 10 deaths and 24 injuries.
