Somali Gunmen Rob U.N.’s Relief Workers : Africa: Teen-agers halt plane on runway, steal passengers’ valuables. And street battle temporarily traps U.N. group.

A group of teen-agers armed with antiaircraft guns stopped a U.N. plane on a runway in the southern city of Kismayu on Monday and robbed the relief workers on board of luggage, money and passports.

In the capital, Mogadishu, some U.N. Children’s Fund workers were temporarily pinned down by a street battle between two clans.

No UNICEF workers were injured, but the incidents show the danger that the many foreign relief workers face trying to feed starving Somalis.

Somalia’s government collapsed with the January, 1991, overthrow of dictator Mohamed Siad Barre, and now clan-based gunmen rule. Gunfights, robberies and car-jackings are common, and relief workers hire armed guards for protection.

Clan fighting has prevented food airlifts to Somalia’s remote areas and prevented boats from using the main ports. Relief agencies in Mogadishu and Kismayu have been forced to cut rations in half.

In Washington, two U.S. senators who have just returned from Somalia said the United States should provide military planes to fly an additional 3,000 U.N. troops immediately to Somalia to protect the aid.

Democrats Paul Simon of Illinois and Howard M. Metzenbaum of Ohio proposed that the cost of the airlift be deducted from $800 million the U.S. government owes the United Nations. They said U.N. Secretary General Boutros Boutros-Ghali has indicated support for that idea.

On Monday in Kismayu, 15 to 20 teen-age gunmen riding a five-ton truck mounted with two antiaircraft guns halted the U.N. passenger plane as it was taxiing for takeoff, a passenger said.

The gunmen threatened to blow up the Beechcraft plane and ordered the six passengers and two crew members to get off. The plane, flying from Mogadishu to Nairobi, Kenya, had stopped to pick up a U.N. official.

Heavy fire broke out between the gunmen and another group of youths carrying weapons who approached the plane from the terminal, said P. V. Vivekanand, the political editor for the English-language Jordan Times and Middle East correspondent for United News of India.

“The shooting scared everybody. We all immediately ducked,’ Vivekanand said. “I have no doubt whatsoever that they would have shot the plane and the passengers if we hadn’t agreed to their demands.”

In the capital on Monday, a gun battle erupted in front of UNICEF offices when members of two clans, the Hawadle and Duduuble, fought over a vehicle one group apparently had stolen from another.

Relief workers hurried to get away from windows and lay on floors during the 20-minute exchange.