The United Nations says tens of thousands of people are fleeing Somalia, making a difficult and dangerous journey to safety in Kenya.

The U.N. refugee agency said Friday about 20,000 refugees have left Somalia for Kenyan camps in the past two weeks.

UNHCR spokeswoman Melissa Fleming has described both the increase in refugees and their condition when they arrive as “shocking.”

Fleming said many of the refugees are walking for days without food or water to get to the Dadaab camp in Kenya.

The U.N. refugee agency has expressed concern about the intensifying violence in Somalia.

The U.N. has said about 50,000 people fled Somalia during the first three months of this year. That compares to about 23,000 Somalis who left during the same period in 2010.