Tens of thousands of refugees fleeing conflict in Sudan are struggling to find sufficient water for their drinking and cooking needs, leading to an unknown number of deaths from dehydration and diarrhea, officials reported Monday.

In the past month, over 35,000 people have fled ground fighting and bombing in Sudan for South Sudan. The war is between Sudan’s military and a rebel group linked to South Sudan. Most of the refugees are women, children and the elderly, as the men generally stay behind to fight. Many of the new arrivals walked two to three weeks to reach the border with South Sudan, and around 40,000 more are believed to be en route to South Sudan. Over the past week, thousands of the new arrivals had to walk 13 miles to find water, and the shortages are becoming more severe.

Tara Newell, an emergency coordinator with Doctors Without Borders, said that water is among the highest priorities in the crisis. “It’s very sad that with this number of refugees that simply having something to drink is our biggest challenge.”

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