With a ragged breath soft as the beat of a butterfly's wing, two-year old Mahmud Mohamed sighed, rolled his eyes upwards towards his mother, and died, succumbing to the effects of the extreme drought ravaging the Horn of Africa.

"My child is gone," his mother Mulmilla said quietly. Then she gently closed his eyes, wrapped the tiny body in a colourful scarf, bound it with scraps of material, and bore it outside to be buried.

Parts of southern Somalia, including war-torn Mogadishu, are reeling from a brutal famine, the first to be declared by the United Nations this century.

Thousands have died, according to the UN, and exhausted nurses in Mogadishu's Benadir hospital barely looked up as Mulmilla left slowly carrying her son.

A dozen severely malnourished babies remained on the long bench reserved for the most extreme cases brought in by desperate parents, many of whom had trekked for days from outside the city to reach help.

The hospital -- a decrepit building without clean water or regular electricity that is the main children's ward for Somalia's capital -- is as good as it gets for those struggling to survive here.

"There are so many coming, and we are doing what we can," said nurse Asli Ali, taking a brief break in between fixing feeding tubes up the noses of skeletal children too weak to eat food normally.

"They come everyday, and many are too sick," she added.

Many, like Mohamed, are arriving too late for anything that the basic services the grossly overstretched hospital can offer.

In the hour before Mohamed passed away, three other children in the cramped ward also died, health workers said.

Like Mulmilla -- who fled the famine-hit Lower Shabelle region to Mogadishu only to find hunger in the displaced camps here -- more than 100,000 people have arrived in the dangerous city to escape drought in recent months.

"There too many to cope with," Ali added, waving at the room, where even wooden office desks are used as hospital beds.

Some simply sleep on the floor: mothers and children use empty cardboard boxes -- once filled with specially nutritious peanut paste packs supplied by the UN children's agency -- as mattresses.

There is no space available to separate children infected with an outbreak of measles -- a common cause of death for children weakened by malnutrition -- from those not infected by the virus.

A sickly cough from a nine-year old on a stretcher briefly raised a thick cloud of flies that quickly settled back onto him.

The stretcher has a hole cut for children sick with diarrhoea, underlining a UN warning that a cholera epidemic could spread swiftly.

Given the number of people crammed inside, the ward was eerily quiet, with children apparently too tired to cry.

Many have come from the dozens of new camps appearing in the war-ravaged city, squeezed inside ruins of bombed-out buildings.

Despite a ramping up of aid efforts and international pledges of support, the situation remains dire.

But outside the capital it is feared to be far worse -- areas under the control of the Al-Qaeda-affiliated Shebab rebels, whose draconian ban on key foreign aid groups is blamed for exacerbating drought into famine.