Scores of Americans, including missionaries and aid workers, streamed out of Haiti on Friday to escape a two-week rebellion that has overwhelmed the impoverished country's north. Many police deserted their posts, and rebels threatened new attacks this weekend.

Later in the day, American and other diplomats handed President Jean-Bertrand Aristide (search) a plan that calls for an interim governing council to advise him, and appoint a prime minister agreeable to both sides.

But both sides were almost certain to reject it -- Aristide because he has said he will not negotiate with the opposition, and the rival leaders because they want Aristide to step down.

Pro-government militants burned 15 homes in the western port of St. Marc overnight, and three people died in the fires, independent Radio Galaxie reported.

A day after the U.S. government urged Americans to leave Haiti, more than 200 people from the United States, France and Canada stood in long lines Friday at Toussaint Louverture International Airport (search), anxious to get out.

"We knew that it was right for us to leave. It's just hard," said Nancy McWilliams, an 18-year-old from Ottawa who abandoned a volunteer job at a children's home in northern Cap-Haitien.

The U.S. government has begun placing air marshals on all American flights in and out of Haiti because of hijacking fears, officials in Washington said. American Airlines said seats were sold out on four of five daily flights to the United States.

American missionary Gerald St. Vincent, waiting for a flight to Miami, said Haiti will resolve its problems "only if they have help from outside sources -- not less help but more."

The uprising began two weeks ago when rebels took the city of Gonaives, and they have since pushed police out of more than a dozen towns in the north. They accuse Aristide of breaking promises to help the poor and of driving the country into chaos while quietly supporting attacks on opponents -- charges the president denies.

The proposal presented Friday reflects heightened international pressure to break the stalemate between Aristide and his opponents after more than three weeks of unrest that has included outbreaks of violence. It would also disarm politically allied street gangs

Also, Caribbean nations appealed to the international community to provide security assistance to end the rebellion.

Foreign Minister Fred Mitchell of the Bahamas, speaking to a special U.N. General Assembly meeting on the situation in Haiti on behalf of the 15-nation Caribbean Community, said the United Nations "has a crucial role to play in developing and executing solutions to this urgent crisis."

But none of the several speakers mentioned brought up the issue of whether to send a U.N. peacekeeping force or any other troops.

Protesters at an anti-government march on Friday vehemently denounced any negotiations that could leave in Aristide power.

"Aristide is a scorpion!" about 1,000 marchers chanted, until they were attacked by Aristide supporters, who threw rocks and bottles and then opened fire.

More than 20 people were injured and at least two were shot, hospital officials and the Red Cross said. One of those shot was a reporter with Radio Ibo, the station reported.

Some foreigners vowed to remain despite the violence.

American missionary Terry Snow, who planned to stay, said six truckloads of pro-Aristide gunmen torched seven houses in his seaside neighborhood in St. Marc. As their houses burned, residents jumped into the sea and gunmen fired into the air to keep them from returning to land, he said.

"Innocent people are being killed and houses are burned down every day and night in St. Marc and the police are doing nothing," said Snow, 39, of Granbury, Texas.

No foreigners have been killed in the uprising which began Feb. 5 and has claimed the lives of more than 60 Haitians, about 40 of them police officers. Armed men have threatened missionaries and journalists.

There are an estimated 30,000 foreigners in Haiti, including about 20,000 Americans. Many of them also have Haitian passports, but it is not known how many.

All 70 Peace Corps volunteers are being pulled out of Haiti. They were in a convoy Friday heading to the Dominican Republic.

France's U.N. ambassador, Jean-Marc de la Sabliere, warned that the chaos compounded by the "depths of despair and of chronic misery ... cannot but lead to a humanitarian catastrophe."

The Pentagon said it was sending a small military team to assess security for the U.S. Embassy and its staff.

"This place used to be full of foreigners. The Peace Corps volunteers would come in from their villages to watch television," said John Leary, an American forestry adviser, motioning at the deserted lounge of the Roi Christophe Hotel in Cap-Haitien.

The new leader of a loose alliance of three rebel groups, Guy Philippe, said he plans to attack Cap-Haitien during celebrations of the pre-Lenten carnival bash that were scheduled to begin Friday and run through Tuesday.

About 60 frightened police officers have barricaded themselves into their station at Cap-Haitien, saying there aren't enough of them and they're too poorly armed to fight. Gangs of armed Aristide supporters built roadblocks and vowed to fight any rebel attack.

Police deserted their posts Thursday in the northern city of Fort Liberte, witnesses reached by telephone said. No rebels were in sight.

A U.S. official said Prime Minister Yvon Neptune sent a letter to U.S. Ambassador James Foley requesting help to strengthen the police, judiciary and restore order.

Secretary of State Colin Powell (search) has said the United States would not object if Aristide agreed to leave office early. Aristide's term ends February 2006, and he has said he will not leave before them.

In Ottawa, Canadian Cabinet Minister Denis Coderre, who will join an international delegation arriving in Haiti on Saturday to mediate on the plan, said "we think Aristide must remain in place."

The violence has raised fears of a mass exodus of Haitians, but the U.S. Coast Guard has said it has not seen any increase in migrants leaving.