By Aaron Maasho
DOLO ADO, Ethiopia (Reuters) - Rasheed Hassan had to walk out on his son when he fled war in his native Somalia to go to neighboring Ethiopia. Two other children had already been shot dead in crossfire near his home.
Fearing for his life, Hassan, 42, walked for eight days, his belongings in a donkey cart, to the refugee camp that has become home to thousands more escaping war and now a second killer -- drought.
"I even left a son behind -- there wasn't enough space," he said, two days after arriving at Dolo Ado, just a kilometer north of the border with Somalia.
The cluster of crowded camps scattered around the town now shelter almost 100,000, but officials say the deadly cocktail of daily bloodshed and a ruinous regional drought will force even more to arrive in the coming months.
The United Nations High Commission for Refugees (UNHCR) and Ethiopia have set up a cluster of camps at Dolo Ado to accommodate the influx of refugees, which officials say has now topped some 1,600 people each day.
"This is the worst humanitarian disaster we are facing in the world," UNHCR head Antonio Guterres said during a trip to the area on Wednesday. "We have one-fourth of the population of Somalia displaced."
The agency is building more camps to hold another 120,000 people as drought ravages the region.
Hospitals in the Somali capital Mogadishu are also reporting more malnourished children among refugee arrivals fleeing the drought. Pastoralist communities in northeastern Kenya face starvation as it continues to engulf the region.
Although the civil war in Somalia has raged for two decades since the downfall of Siad Barre's rule, fighting between the internationally backed government and the rebels has intensified during the past year, with civilians bearing the brunt.
Hassan left behind the whistles of incoming mortar fire that had shaken the town of Bohol Bashir for days, and fled the house-to-house searches and bloody street battles as government troops fought al Shabaab, a group that claims links to al Qaeda and fights to topple Somalia Western-backed government.
"I was just a trader and had no involvement in the conflict so I chose to stay," he said.
"But then two of my children died, caught in the cross-fire as they fought it out just meters away from our house," Hassan said, shrugging his shoulders in desperation at the loss of Mohammad, eight, and Abdi, 12.
On the outskirts of the arid town of Dolo Ado, a sea of white tents with large U.N. initials on top, flank a "transit point" for new arrivals as emaciated residents line up to fetch the day's ration of food under a blazing sun.
After surviving without food for days in the wilderness, some worry that the camps do not have sufficient capacity to feed their children.
"My children are becoming weaker every day. We haven't received much since we arrived here three days ago," said Dindo Ali, a mother of four.
Part of the problem, according to some experts on the ground, is that most of the refugees arrive with medical conditions owing to food shortage. Refugees from southern Somalia say they have not had a single harvest in two years.
The number of people in need of food assistance across the region is expected to rise to 10 million from previous forecasts of 6 million, the World Food Programme has said.
Drought and fighting have put about 2.85 million people -- a third of Somalia's population -- in need of humanitarian assistance, WFP's Emilia Casella said.
"There's a large occurrence of severe malnutrition among refugees aged under five," said Jerome Souquet of Doctors Without Borders. "We also have high cases of diarrhea and respiratory disease. The lack of sufficient resources forces them to come back after receiving treatment."
UNHCR's Guterres said the crisis in Somalia had been overshadowed by other global events, and called for urgent support and also commitment to end the war in the country.
"The Arab Spring has created an enormous interest on the internationally community, but all our operations in Africa are underfinanced -- there has been not enough investment in addressing humanitarian issues," he said.
(Editing by James Macharia)