MOGADISHU, Somalia — Dozens of heavily armed government security forces stormed a U.N. compound Wednesday and spirited away the official overseeing emergency food aid for Somalia's war-ruined capital, prompting the agency to suspend distributions.

The World Food Program called for the immediate release of Idris Osman, a Somali in charge of the agency's efforts to help feed tens of thousands of people in Mogadishu. The city is in shambles after more than a decade and a half of chaos and war.

"In the light of Mr. Osman's detention and in view of WFP's duty to safeguard its staff, WFP is forced immediately to suspend these distributions and the loading of WFP food from our warehouses in the Somali capital," the WFP said in a statement.

WFP said between 50 and 60 Somali government security forces, some in uniform, entered the compound and seized Osman without firing any shots. Osman was being held in a cell near the presidential palace, the agency said.

At U.N. headquarters in New York, U.N. Secretary-General Ban Ki-moon demanded Osman's immediate and unconditional release and called the entry into the U.N. compound "forceful and illegal," U.N. deputy spokeswoman Marie Okabe said.

Interior Minister Mohamed Mohamoud Guled denied that government forces carried out any operation at the U.N. compound. But he said the WFP had recently distributed food aid without consulting the government. In recent months, the government has blocked aid distributions to areas perceived to be adversarial.

Citing staff safety, the World Food Program said it was suspending distribution for a feeding program that began Monday using government-approved mosques. It was aimed at easing the plight of 75,600 people in Mogadishu.

The U.N. Office for the Coordination of Humanitarian Affairs estimates some 1.5 million Somalis are now in need of food aid and protection — or 50 percent more that at the start of the year — because of inadequate rains, continuing internal displacement and a potential cholera epidemic.

Somalia has not had a functioning governments since 1991, when rival warlords overthrew dictator Mohamed Siad Barre and then turned on each other.

Mogadishu has been plagued by fighting since government troops and their Ethiopian allies chased out the Council of Islamic Courts in December. For six months, the Islamic militia controlled much of southern Somalia and remnants have vowed to fight an Iraq-style insurgency. Thousands of civilians have been killed in the fighting so far this year.

The detention of the WFP official followed some of the heaviest fighting in weeks in the capital. Overnight, at least eight civilians and one policeman died in a battle between Islamic insurgents and policemen that lasted for hours, residents and police said.

The fighting began when about 100 insurgents blasted a police station in southern Mogadishu with heavy machine-guns and rocket propelled grenades, residents said. The civilians died when mortar rounds crashed into their houses.

"Buildings shuddered and weapons exchanged by the two sides illuminated the sky of the city," said Abdullahi Hussein Mohamud, who also said some mortars landed near his home some distance from where the battle took place.

Abdi Haji Nur, a businessman, said that the insurgents captured the station, forcing about 30 policemen based there to flee.

Gen. Yusuf Osman Hussein, director of police operations in Mogadishu, denied the insurgents seized the station, saying policemen repelled "elements of peace-haters" and lost one of their colleagues during the fighting.

In Somalia, as in many other war-ravaged African nations, food aid and other humanitarian efforts have taken on political significance. During chaos in Mogadishu in the 1990s, clan militias kept food from hungry residents, seeking to control the populations and feed their own fighters.

In Sudan, the WFP said Wednesday that three truck drivers working for the agency were killed in recent days while delivering food aid to the western region of Darfur. Fighting in Darfur broke out in 2003 between ethnic African rebels and Sudan's Arab-dominated central government.

In Liberia and Sierra Leone, two West African nations that suffered under long civil wars, food aid was often captured by rebel or government-militia forces. In Liberia, rebel fighters would raid U.N.-run refugee camps and steal sacks of grain, abducting camp residents to use as porters for their booty.

Aid officials in those countries said it was inevitable that some food aid would end up in the hands of combatants, but said that should never be a reason to stop efforts to feed hungry civilians.

In many of Africa's poorest countries, food aid is the main source of nutrition for many citizens.