By LYDIA POLGREEN and CHRISTOPHER MARQUIS
 
CAP HAITIEN, Haiti, Feb. 23 — Rebel soldiers consolidated their grip here in Haiti's second largest city on Monday, sending truckloads of armed men to patrol the streets and going from house to house arresting pro-government militants, while political opposition leaders in the capital, Port-au-Prince, asked for 24 hours to mull over a peace plan presented by the Bush administration and its allies.

"They're moving in our direction, but we're not there yet," said an administration official briefed on the talks.

Opposition leaders have told Secretary of State Colin L. Powell that they are having a hard time committing to the proposed power-sharing agreement, which has been accepted in principle by President Jean-Bertrand Aristide. The problem, they say, is that their radicalized followers are adamantly opposed to allowing Mr. Aristide to continue in office, even in a titular role.

In Cap Haitien, residents pillaged and burned any symbol they could find of Mr. Aristide and his party, Lavalas, exacting chaotic revenge on a government they said had terrorized them. Looters took the benches and lawyers' tables from the courthouse before setting it on fire, and helped themselves to the contents of houses of government supporters.

"Lavalas is gone, they ran away," said a man who struggled to strap a dining chair he had taken from the house of a Lavalas partisan to the back of his bicycle while balancing a stereo speaker under his arm. "Now this is mine."

In Port-au-Prince, 50 marines arrived Monday afternoon to secure the United States Embassy, while some government ministers began casting about for secure hiding places and others vowed to repel the insurgent advance.

Louis-Jodel Chamblain, leader of the rebel troops, said their capture of the northern city whose outskirts were the birthplace to the slave uprising that created the world's first black republic 200 years ago, is a symbol of their intention to wrest control of the entire nation and expel the embattled president. "Cap Haitien is a symbol of Haiti's freedom," Mr. Chamblain said. "This fight is to liberate the Haitian people under the regime of Jean-Bertrand Aristide."

But there were indications on Monday that the opposition could still accept the peace plan, which was put forth this weekend by Roger F. Noriega, the assistant secretary of state for Western Hemisphere affairs.

Over the weekend, Mr. Powell called a leader of the opposition, André Apaid, to urge him to sign onto the agreement, and American diplomats made similar contacts with rebel leaders, officials said. "We told them if they need more time, to take more time," a senior State Department official said.

Under the proposed peace accord, put together by the United States, France and the Organization of American States, a three-party commission would be set up to appoint a new prime minister and a government of national unity. Mr. Aristide would remain as president.

The international community would take part in the commission and serve as a referee between the president and his enemies, according to officials briefed on the offer, which has not been made public.

The new government would lay the groundwork for parliamentary elections some time later this year and presidential elections toward the end of Mr. Aristide's term in 2006. It would also oversee a changeover in the leadership of the police and set up ground rules for opposition protests and rallies.

Whatever happens in the peace talks, the taking of Cap Haitien has for now put the rebels in control of not only half the country but also Haiti's heartland, where the original slave uprising started. The rebels also control Gonaïves, the city where Haiti's freedom from France was proclaimed on Jan. 1, 1804.

Not even two months ago, Mr. Aristide presided over a chaotic bicentennial celebration in Gonaïves, at which he cast himself as the true heir to Haiti's slave soldiers. Those fighters delivered such rattling defeats to Napoleon's imperial army that the French emperor gave up his American colonial ambitions, selling the Louisiana Territory to the United States.

But on Monday, as rebel soldiers patrolled the city and residents sacked the houses of the president's allies, Mr. Chamblain, the rebel military leader, cast Mr. Aristide in the role of the colonial oppressor. "Our objective is to liberate Haiti because we consider Aristide like LeClerc," Mr. Chamblain said, referring to Gen. Charles LeClerc, Napoleon's brother-in-law, whom the emperor sent to quell the slave revolt.

It was a stark reversal of fortune for Mr. Aristide, who had counted Cap Haitien as one of his strongholds. On Saturday, the city's mayor, Wilmar Innocent, boasted that pro-government militants would easily repel any rebel attack.

"The population armed itself and are taking actions to protect the city," Mr. Innocent said in an interview in the city hall on Saturday, smiling broadly and swigging a bottle of Prestige, the Haitian beer. "They are ready to face the rebels." But by Monday, Mr. Innocent had disappeared, and residents torched his house, after first looting it of everything of value.

After emptying the city's port of rice and other goods, looters set their sights on a warehouse used by the United Nations to store food for the quarter-million people who depend on aid to survive. Hundreds of people squabbled over sacks of beans, jugs of vegetable oil and cans of fish.

The city has been cut off from the capital since Feb. 5, when rebels took the city of Gonaïves and cut off the main north-south road between Cap Haitien and Port-au-Prince. The blockade has driven up food prices, and gasoline for cars and generators is in short supply. With aid stocks now gone, aid agencies raised the specter of a widespread relief crisis, as people run out of food and hospitals deplete their supplies of medicines.

Soldiers arrested anyone suspected of being a pro-government militant. One such man, Jean-Bernard Prevalis, lay face down in the back of a pickup truck, arms handcuffed behind him. Blood streamed down his face from a gash in his forehead. He insisted that he was not a government militant.

"I am a bricklayer," he said. Soldiers said they had identified the militants, known here as chimères, with the help of city residents.

"The people show us their houses," said Claudy Philippe, a 32-year-old rebel soldier who sat atop a pickup truck, a gas mask on his head and a cell phone strapped to his boot. "Those we arrest, maybe there is a chance the people will have mercy on them." Despite the mayhem there was little panic, and people did not appear to be fleeing the city.

"We are taking control," said Guy Philippe, the rebel leader and main spokesman. "We are securing the city. No one needs to be afraid."

At the city's airport, which shut down on Monday, Solomon Ronel gestured at the runway, which was carpeted with unused boarding passes and flight manifests. He said he had hoped to fly to the capital so he could get home to Miami, where he works at a gas station. He came to Haiti 15 days ago to arrange for his wife and son to move to Miami with him.

"The rebels are not doing any good," he said. "I don't get into politics. I am just living and working hard."

Lydia Polgreen reported from Cap Haitien for this article and Christopher Marquis from Washington.