Rebels Free Foreigners in Liberia : Civil war: A West African force prepares to go to the country to enforce a cease-fire.

One of the two rebel forces besieging Monrovia, the capital of Liberia, Wednesday freed a group of foreigners, including an American, who had been seized in an attempt to provoke foreign intervention in the civil war there.

It was not made clear how many foreigners had been held by the rebel faction, headed by Prince Johnson, but a spokesman at the British Foreign Office announced in London that its embassy in Monrovia indicated that all were now free.

The spokesman said the foreigners were on the way to downtown Monrovia and “not in our hands.”

On Tuesday, Johnson had exhibited eight foreigners seized at a resort hotel and told reporters: “What this country really needs is the peaceful intervention of the United States (or other African nations). If they don’t intervene, I will attack the American Marines.”

He referred to a detachment of about 200 Marines who were put ashore Sunday to oversee the evacuation from Monrovia of Americans and other foreign nationals.

Meanwhile, five West African nations began organizing a joint force to go into Liberia and enforce a cease-fire on the two rebel factions and the government forces of President Samuel K. Doe.

The mission was approved Tuesday by the leaders of Nigeria, Ghana, Guinea, Gambia and Sierra Leone, who were concerned that the war was turning Liberia into a “slaughterhouse,” in the words of Dawda Jawara, president of Gambia and chairman of the Economic Community of West African States. The joint force will be commanded by a Ghanaian with a Guinean deputy.

Reuters news service reported that the force will have 2,500 men and will arrive in Liberia in 10 days. An armed forces spokesman in Accra, Ghana, said that country will contribute 1,000 troops, according to Reuters, which also reported that Nigeria will send 700 men, Guinea 550, Sierra Leone 350 and Gambia 105.

Charles Taylor, head of the larger rebel force, has about 10,000 men behind him and has said he intends to oppose any intervening force.

Although there was still some confusion about the number of foreigners seized by Johnson’s men, estimates have ranged up to 22. At Johnson’s news conference at his headquarters outside Monrovia, he identified only the eight, among them Chris Mendes, who is said to be a mining engineer from Sacramento. The others were three Britons, two Germans, a Dutchman and an Argentine.

Lebanese officials in Beirut told the Associated Press there were 10 Lebanese in the group.

There is a substantial number of Europeans engaged in mining and timber in Liberia. Monrovia also has a large Lebanese community, which dominates commerce and trading there as in other West African countries.

Doe, who seized power in a coup in April, 1980, and claimed the presidency after a fraudulent election in 1985, remained besieged in his Monrovia mansion as scattered fighting continued throughout the capital.

The rebellion began last Christmas Eve, when Taylor, a former Cabinet minister under Doe, entered Liberia from Ivory Coast with a handful of men. He relied for recruits on members of the Gio and Mano tribes, who resented what they see as Doe’s favoritism on behalf of his own Krahn tribe.

Eventually the fighting took on a tribal character, as Taylor’s and Doe’s men inflicted heavy casualties on civilians in the rival tribal groups. Taylor is neither Gio nor Mano, tracing his lineage largely from the freed American slaves who established Liberia as an independent country in 1847.

Johnson split his faction from Taylor’s National Patriotic Front in February and reached the center of Monrovia first, about a month ago. Since then, he and Taylor have spent as much time fighting each other as the government. Meanwhile, Monrovia’s water and power supplies have been cut off for a month, and food is becoming scarce in the capital.