(CNN) -- The only hospital on the border between Sudan and South Sudan is running short of supplies as rebels menace oil fields in the region, a photographer who visited the isolated area told CNN.
Pete Muller, a photographer and multimedia reporter based in Juba, Sudan who visited the isolated area near the Blue Nile and Nuba Mountains a few weeks ago, told CNN the area was heavily militarized and medical supplies were being depleted.
"On my first day we came under bombardment and were pinned down in a riverbed for about 45 minutes during the hottest part of the day. It seems that the war at the time was dominated by Sudanese Air Force (SAF) bombers. All the shops were closed the markets were empty. Ground fighting was minimal and there were phases of SPLA/M-N checkpoints in between the front line and the town of Kurmuk," he said referring to the Sudan People's Liberation Movement North.
The SAF began launching aerial attacks against rebels in the region shortly after the president of Sudan ordered the dismantling of joint units which had integrated Southern Sudanese and Sudanese military fighters within the region of Southern Kordofan.
Muller told CNN that as a result of unrest the only hospital in the vicinity of fighting is running short on medical supplies.
"The Kurmuk hospital is seriously overstretched. The medical director said they had approximately one week's worth of supplies left. But with the recent offensive on Kurmuk, I imagine that they are depleted," says Muller.
The Southern Kordofan, Blue Nile State and Nuba Mountain regions straddle Sudan and South Sudan's geographical and political lines. Although these territories are geographically part of Sudan, its population has faced "exclusion, marginalization and discriminatory practices that have resulted in their opposition to the Sudanese government," according to the U.N. Office of the High Commissioner for Human Rights.
Muller says although he did encounter SAF forces on the ground he did meet plenty of Sudanese People's Liberation Army North (SPLA-N) rebels.
"I am not sure about recruitment procedures with the SPLM-N," said Muller, "but I did not get the sense that they were coercing people to join. SPLA-N rebels ranged in age from approximately 13 into their 60s," he added.
Both Sudan and Southern Sudan say neither of their governments are supporting rebels. But the conflict between government troops and rebels is threatening stability in the region because the two countries have yet to agree on how to handle the formerly shared oil industry located on border territory.
A total of 92.6% of Sudan's export revenue is based in oil fields in the region. These fields were not discovered until after the 1972 peace agreement was signed. The Comprehensive Peace Agreement (CPA) helped to reduce the conflict after almost four decades of civil war by equally splitting oil profits between the north and south, granting the south autonomy and incorporating the southern guerrilla movement into the national army.
More than 73,000 people have been displaced from the border territory between Sudan and South Sudan because of the violence, according to the United Nations.
It is nearly impossible for relief workers and journalists to get close to the Blue Nile and Nuba Mountains. The government of Sudan cites security concerns as its reason for restricting access to the Southern Kordofan region.
CNN's Sarah Jones contributed to this report