Abdulqadir Abdullah Ali suffered serious nerve damage to his leg during the long siege of the Sudanese city of el-Fasher because he could not get medicine for his diabetes.

The 62-year-old walks with a heavy limp, but he was so panicked when fighters from the paramilitary Rapid Support Forces (RSF) finally captured the city in the western Darfur region, he felt no pain as he ran.

The morning the RSF came there were bullets, many bullets, and explosives going off, he says.

People were out of control [with fear], they ran out of their houses, and everyone ran in different directions, the father, the son, the daughter - running.

The fall of el-Fasher after an 18-month siege is a particularly brutal chapter in Sudan's civil war.

We found Mr. Ali wandering around the camp, located in the desert about 770km (480 miles) north-east of el-Fasher, near the town of al-Dabbah. He was trying to register his family for a tent.

They [RSF fighters] were shooting at the people - the elderly, the civilians, with live ammunition, they would empty their guns on them, he told us.

Mr. Ali said he ran when he could, crawling along the ground or hiding when the threat got too close. He managed to get to the village of Gurni, a few kilometres from el-Fasher.

Gurni was the first stop for many who fled the city, including Mohammed Abbaker Adam, a local official in the nearby Zamzam camp for displaced people.

Mr. Adam retreated to el-Fasher when Zamzam was overrun by the RSF in April, and left the day before they captured the city in October.

The road here was full of death, he said.

They shot some people directly in front of us and then carried them and threw them far away. And on the road, we saw dead bodies out in the open, unburied. Some had lain there for two or three days.

Some of those who did not take the long trek to al-Dabbah made it to a humanitarian hub in Tawila, some 70km from el-Fasher. Others crossed into Chad. But the UN says less than half of the 260,000 people estimated to have been in the city before it fell have not been accounted for.

Mr. Adam said the fighters also raped women, corroborating widespread accounts of sexual violence. They would take a woman behind a tree, or take her far from us, out of sight, so you wouldn't see with your own eyes, he said. But you would hear her shout: 'Help me, help me.' And she would come and say, 'They raped me.'