After a period of relative calm in Muhajariya, two months of open combat and tense in-fighting between a shifting panoply of armed groups broke out on October 2. Ordinary civilians often found themselves as primary targets. In the following weeks violence enveloped the area to the south and east of the town, forcing more and more people to flee.

After a series of violent attacks over the past two months, at least 50,000 civilians in south Darfur have fled to the arid countryside. Villages have been burned, civilians shot, water points and food stocks destroyed. Médecins Sans Frontières (MSF) is providing surgical assistance to the wounded, has set up fixed and mobile health clinics, and is distributing plastic sheets, blankets and food.

Under a thorny acacia tree in the dry countryside of south Darfur, a few families seek relief from the scorching sun. Men, women and children are sitting among the meagre possessions they were able to rescue when they fled an attack on their home village: plastic jerry cans, a few pots and pans and some rush mats. They have tied a blanket to the branches above their heads, creating a small patch of shade in the dust.

MSF mobile teams, travelling out of the town of Muhajariya, encounter hundreds of families like these, living outside under bushes and trees, scattered over tens of kilometres of inhospitable terrain. Water is scarce - the dry season has started - and some are forced to drink water from stagnant pools they share with the cattle.

During consultations, MSF's doctors and nurses find signs of deprivation and exposure. Diarrhoea is increasing rapidly; skin diseases are multiplying; some of the children already have respiratory tract infections because of the cold nights.

At least 50,000 civilians fled to the precarious refuge of the countryside after a series of violent attacks in Muhajariya and the surrounding area. For many of them, it was not the first time they had to leave - they had been displaced from other regions and were already living under difficult conditions in displaced camps on the edge of town.

After a period of relative calm in Muhajariya, two months of open combat and tense in-fighting between a shifting panoply of armed groups broke out on October 2. Ordinary civilians often found themselves as primary targets. In the following weeks violence enveloped the area to the south and east of the town, forcing more and more people to flee.

When MSF's mobile teams were able to move around, they found civilians shot and beaten, villages largely burned to the ground, water points damaged beyond repair, food stocks destroyed, and despair over suddenly shattered lives and communities.

MSF found an elderly man lying under trees to the east of Muhajariya with a gunshot wound and an open fracture of the femur. He described how his home in the village of Angabo was attacked on November 13.

"Ten people came inside," he said. "They asked me who I was and if I had a weapon, then they shot me, took all of my money and burned my house. I was still inside when they set fire to it."

For many, the violence came without warning.

"I was in my home when I heard gunfire," a man who fled southwards told the MSF team. "I stayed where I was and the next thing I knew I was shot! It was my hand that was hit. I saw two vehicles with fighters on the back of them - there must have been 15 on the back of each vehicle. They were just shooting and shooting at my friends and into our homes."

The violence has been continuing intermittently since the beginning of October. On some occasions, people who fled were attacked once again, forcing them to wander the area in a desperate search for security. The MSF-supported clinic in Muhajariya includes surgical services, and is receiving a steady flow of victims who require specialised medical care.

Since the start of the clashes, 131 people were treated for war trauma. Of these 107 had gunshot wounds. One quarter were civilians. At times, even patients in the Muhajariya clinic feel unsafe. During a bout of fighting and reprisals on October 23, when MSF staff were forced to seek shelter, 15 patients fled from its hospital wards.

Perhaps most worrisome is the way in which this armed conflict has, at times, split populations along local ethnic lines, enflaming tensions in the region. The ethnic dimension has prompted attacks on villages or displaced camps, meaning that civilians without any relation to the military have been made direct targets.

This complicates the already disastrous humanitarian situation, for example making displaced people afraid to return home even though the situation may calm, or for MSF to worry that its work may jeopardize the safety of its national staff by bringing them across community divides.

Every day MSF staff are confronted with the suffering, despair and misery of ordinary people who are nevertheless trying to continue their life in all possible ways with little resources.

"I can't sleep thinking about these people," said Jonathan Henry, MSF's Project Coordinator in Muhajariya. "One woman told me she was at home with her seven children when the fighting started. Armed men burnt her house and all her property. They shot at her children as they ran to get away. Now she's displaced and she wants to get as far away from Muhajariya as quickly as possible. I just don't see where they can go."

Due to their rapid flight into this harsh environment, with little or no time to assemble and carry provisions, the displaced urgently need assistance. Where they feel safe, they collect water by digging shallow wells in dry riverbeds.

The MSF team is increasing the supply to the most vulnerable by trucking water in and repairing local water systems. But water is running out in many places because so many people and cattle are drinking it.

"A week, that's how long the water will last. After that we will move on to find more water but I don't know where we will go," said a 16-year-old girl, who fled while attackers burned the village of Muturwed on November 12. She told MSF four of her relatives were killed, and that her family has been living under a tree ever since.

Food is running out as well. The rainy season was good this year so there is promise of a large harvest, but most people are too afraid to return. MSF teams travelling in the area came across fields partially harvested, the rest slowly spoiling. MSF staff have been treating people who were wounded when they went back to till their fields.

Due to the continuing insecurity there is a real risk that the harvest will be lost. The United Nations and aid agencies have distributed food, but the shifting situation and peoples' continued movements make it impossible to ensure that all people are getting the food they need.

There are no places where displaced people can seek healthcare. Their general health status is precarious, and can be expected to worsen given their living conditions. Over the last few weeks MSF has; established a clinic in Sileah (36 km south of Muhajariya) in order to provide medical assistance to the estimated 17,000 displaced people who have gathered there; is conducting nutritional assessments; and started a measles vaccination campaign for children aged six months to five years old.

MSF has distributed 4,500 pieces of plastic sheeting, 7,300 blankets and over 1,000 packages of high-energy biscuits. Even counting the efforts of other aid organisations, the United Nations and the Sudanese government, tens of thousands of people still remain in critical need of humanitarian assistance, particularly for basic shelter items, food and water.

Over the past few days, renewed attacks have intensified the fighting between rival movements, leading to more civilian deaths and threatening the delivery of MSF assistance to areas outside of Muhajariya. Some of the displaced have been forced to return to the town. Assessing the gravity of the fighting is beyond MSF's scope, but the surgical team in Muhajariya treated 59 gunshot wounds alone in the three days after November 29.

Whether caught up in this violence or deliberately targeted, these people, especially the ones living in the open, must make life or death decisions about how to keep their families safe, find food or water, and grieve their lost relatives or homes.

"What can we do for the woman who smiles from her bed under the tree in the middle of nowhere?" asks Giles Hall, a nurse working as part of the mobile clinic team. The mother proudly showed the bundle in her arms, a 13 day-old baby girl, her age easily remembered because it was 14 days before that she fled her village in fear of the violence that followed soon afterwards. The baby girl was born under a tree and started her life as a displaced person.