As parts of East Africa contend with what is being called the worst continuous drought in 60 years, aid camps are overflowing even while other camps stand empty.

A drought occurring in the region where Ethiopia, Kenya and Somalia intersect has sent tens of thousands of people pouring into refugee camps in search of food.

The World Food Program says around 10 million people in the Horn of Africa currently require food aid. In Ethiopia alone, 4.5 million are in need of aid -- a 40 per cent jump over last year.

One camp, Dadaab, located in northeast Kenya, has become the largest refugee camp in the world. Since 1991, thousands of refugees from the Somalian civil war have lived there.

Though the camp was designed to house 90,000, more than 380,000 refugees are now inside, with about 1,400 arriving and trying to get in every day.

Refugees from Somalia are walking for days or weeks to reach the camp, with many of dying en route.

Faduma Sakow Abdullahi, a 29-year-old mother of five, came to a Kenyan camp from Somalia to escape starvation. But only a day before they arrived, two of her children – aged four and five – died of hunger and exhaustion.

At first, she thought the boy and his younger sister were sleeping. She was later forced to leave them unburied under a tree and continue trekking on with her baby and her two other children, aged two and three.

"I never thought I would live to see this horror," she told The Associated Press.

Over the course of her 37-day trek to Dadaab, she saw more than 20 children either dead or unconscious along the roadside.

For many, the situation is just as dire.

After touring the camp Sunday and watching the new arrivals, the chief of the UN's refugee agency said he was stunned.

"I must say that I visited many refugee camps in the world. I have never seen people coming in such a desperate situation," Antonio Guterres told reporters.

"Here, in the outskirts of the Somali refugee camp of Dadaab, we have the poorest of the poor, the most vulnerable of the vulnerable in the world."

Meanwhile, a new camp called Ifo II, which was built to try to ease the overcrowding in Dadaab, lies empty, even though water systems, latrines and health care facilities there are ready to go, the aid agency Oxfam reports.

Kenya's government approved the construction of the new camp two years ago, but it has recently refused to allow people to move in, for fear that refugees will settle there permanently. Another planned extension known as Ifo III has also stalled.

The new arrivals are now taking shelter in basic tents outside the camp boundaries, with limited access to clean water or toilets.

"It is tragic that vulnerable families are trapped in limbo, forced to endure appalling conditions while there are fully functioning services right next door. Their basic needs are being ignored," Joost van de Lest, head of Oxfam in Kenya, said in a statement Monday.

"Women and children have made the most incredible journeys, walking for weeks through the desert and braving hunger and attacks by armed robbers and wild animals, to get to the camps in Kenya. They arrive extremely weak and malnourished, and the least that we can do is ensure that there is water, food and care for them when they get here," said van de Lest.

The three-way border of Kenya, Somalia and Ethiopia is a nomadic region where families depend on the health of their livestock. But after successive seasons of no rain, many families have little food to offer their cattle, goats and camels, leading to mass die-offs.

Elizabeth Byrs, spokeswoman of the UN Office for the Coordination of Humanitarian Affairs, told a media briefing last week that two consecutive poor rainy seasons have resulted in one of the driest years since 1950-51 in many pastoral zones. She added there is "no likelihood of improvement (in the situation) until 2012."

The ensuing food crisis now affects more than 11 million people and is being called the worst food crisis of the 21st century.

A UN map of food security in the eastern Horn of Africa shows large swathes of central Kenya and Somalia in the "emergency" category -- one phase before the fifth and worst category of catastrophe/famine.

With reports from the Associated Press