(CNN) -- Two bombs hit a hospital run by Doctors Without Borders in the war-torn South Kordofan region of Sudan on Monday, destroying the emergency room, pharmacy and hospital kitchen.
The humanitarian group blames Sudan's army for the attack.
"We are shocked that a medical facility can be bombed, especially since it was clearly identified with a flag and a medical red cross on the roof," the organization's Brian Moller said in a statement.
"We also had previously communicated the hospital's position to the authorities in Khartoum," he said, referring to Sudan's capital.
The hospital is in the village of Farandella, where the aerial bombing injured six people, including one hospital worker, Doctors Without Borders said. They were treated at the hospital, which remains operational despite extensive damage, the group said.
Sudan's army denies bombing the hospital.
"Our targets are not civilians," Col. Al-Sawarmi Khalid Saad, a spokesman for Sudan's armed forces, told CNN.
"There is no way our aircraft is involved in this hospital attack. We did not bomb any hospital. We have no reason to attack and destroy any hospital," he said.
Sudan's government has been fighting rebels in the Kordofan region.