Additional reporting by Megan Rowling

Millions of people could go hungry as Somali pirates stage increasingly bold attacks on aid ships off the Horn of Africa, the World Food Programme has warned.

Experts say there is little aid groups can do to reduce the risk in the short term. But they argue that renewed international attention on Somalia could ease the humanitarian crisis there if it addresses the root causes of why so many young men resort to hijacking ships for a living.

The threat to aid shipments has risen as pirates have begun targeting ships further out to sea. On April 8, a gang attacked the U.S.-flagged Maersk Alabama, which was carrying 400 containers of food for aid agencies including the U.N. World Food Programme, about 500 km (300 miles) off Somalia.

On Tuesday, a Togo-flagged ship heading to Mumbai to pick up WFP food was hijacked some 700 km off Somalia, and a U.S.-owned ship loaded with 27,000 tonnes of food aid was attacked on its way to the Kenyan port of Mombasa by pirates with rocket-propelled grenades and automatic weapons.

"If ships are going to be hit as they are heading to Mombasa, we could see in the coming months millions of people going hungry if food assistance is delayed for extended periods," WFP spokesman Peter Smerdon said.

This year, the U.N. food aid agency aims to feed 3.5 million people in Kenya, 3.5 million in Somalia and 970,000 in the Karamoja region of northeastern Uganda, where drought and high food prices have brought widespread hunger.

It relies on Mombasa as a key entry point for food supplies for eastern and central Africa. In 2008, more than half a million tonnes of food arrived there on 200 ships.

The Maersk Alabama's crew managed to fight off the pirates and sail to Mombasa as planned. Smerdon said the cargo's safe arrival was vital for 315,000 Somali refugees in Kenya whose rations are already being cut because of a shortfall in funding.

"You could argue that the most crucial shipping passing off the Somali coast is shipping that is carrying food aid - even if it's destined for Kenya to be repackaged to send to Somalia or other areas," said Roger Middleton, a Somalia expert at London's Chatham House think tank.

"I don't think it's particularly more vulnerable than a ship carrying palm oil or spare parts for cars but obviously, if it's hijacked, the consequences for people are more severe."

LIMITED OPTIONS TO PROTECT AID SHIPMENTS

WFP has been grappling with the threat of Somali pirates for at least two years. Ships carrying its aid to ports in Somalia have been accompanied by naval escorts since November 2007 - currently provided by the European Union - and there have been no attacks on these protected boats.

But the Maersk Alabama did not have an escort because it was taking food to Kenya rather than Somalia. It is the first ship carrying WFP food to Mombasa to be hijacked.

Chatham House's Middleton said that with the pirates widening their operating area beyond the Gulf of Aden - now striking hundreds of kilometres into the Indian Ocean - ships heading from South Asia to east African ports were particularly vulnerable.

He said the international community would struggle to provide the same level of military protection to vessels in the Indian Ocean as in the much smaller Gulf of Aden.

"If you wanted to start escorting every aid ship going anywhere near Somalia, you'd need a massive increase in the naval presence," he added.

WFP's Smerdon said plans were under discussion for a navy patrol backed by aircraft that could spot pirate activity across a wide area, providing a mobile security net.

U.S. aid groups in particular fear their shipments may be targeted because pirates have threatened to take revenge on the United States and France after several of their comrades were killed by the two nations' forces in hostage rescue operations.

"Up to 75 percent of shipments from the United States are supposed to be on ships under U.S. flags," explained Pat Engers, director of shipping for Catholic Relief Services, which had 49 containers on the Maersk Alabama holding wheat for feeding programmes in Rwanda. "Now that pirates are targeting U.S. ships, that will complicate matters. This is the kind of rule that cannot easily change."

Middleton said that, despite the surge in pirate attacks, sea transportation remains the most efficient - and cheapest - method of getting aid to the region, particularly into countries like Somalia where insecurity makes land and air routes dangerous.

This leaves aid agencies with little choice but to swallow the extra costs arising from the heightened risk of attacks. Middleton said insurance has become around 10 times more expensive for ships using routes near the Horn of Africa since 2007, and travelling at full speed to deter pirates requires more fuel.

WFP says it now costs hundred of millions of dollars more to feed the same number of people compared with a year ago because of the problems in shipping aid and high food prices.

TACKLING PIRACY ON LAND

Most aid agencies doubt Somali piracy can be stopped simply by stepping up naval patrols or trying to freeze the assets of the gangs extorting ransoms from ship owners - mainly houses and camels.

"The world seems to be missing the eye of the storm which is not piracy but the crisis on mainland Somalia," said Amanda Koech, World Vision's spokeswoman for Somalia. "Without solving the problems in Somalia, piracy will still go on."

On Wednesday, U.S. Secretary of State Hillary Clinton called for a coordinated international effort to fight piracy off the Horn of Africa, including cracking down on pirate bases and decreasing incentives for young Somali men to engage in the lucrative crime. Washington has also indicated it will help pay for the fledgling Somali government's domestic security force.

"If because of this, the United States and other donor states engage fully in helping Somalia function as a state that's developing and providing for its people, then piracy will have had a silver lining," Middleton said, adding that the anarchic country needs a police force to deal with its sea-faring gangs and a functioning state to provide jobs and business opportunities for its unemployed youth.

But not all aid groups are convinced the surge in international attention will benefit Somali's long-suffering people, fearing commercial interests may outweigh humanitarian concerns.

"As the world focuses on the piracy issue at sea, there is a risk of shifting focus away from the plight of hungry people inside Somalia," warned Oxfam spokeswoman Andrea Pattison.

And some worry that fresh moves to crack down on pirates could make an already dire security situation even worse.

"We are concerned that an international effort to fight piracy may result in a backlash for aid agencies which are helping desperate people inside Somalia," said World Vision's Koech.

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