After blocking a march route with flaming barricades, supporters of President Jean-Bertrand Aristide threw stones at opposition demonstrators Thursday, forcing them to cancel a mass protest.

The clash came a day after Aristide vowed to stay in office, despite international criticism and calls for his resignation by a bloody revolt that has spread to dozen towns and cities and left 49 dead.

"We don't want confrontation," opposition coalition spokesman Mischa Gaillard (search) said on independent Radio Metropole (search). "The police have not done their duty to serve and protect. Since our strategy is a peaceful one ... we have cancelled the demonstration."

Critics including the U.S. government have accused Aristide of blocking similar demonstrations and, despite his protestations against violence, inciting police and his supporters to attack opponents.

Aristide has blamed the opposition for the recent bloodshed, accusing it of sponsoring a former criminal gang and ex-soldiers of the disbanded Haitian army in their deadly revolt moving through western coastal towns along the Caribbean Sea.

"They suffer from a small group of thugs ... acting on behalf of the opposition," Aristide said Wednesday at his first news conference since gun battles between rebels and police erupted Feb. 5.

Aristide's opponents have distanced themselves from the fighting, although they — like the insurgents — want to oust the president. "Our movement is a nonviolent movement," Apaid said Thursday.

The president repeated his determination to remain in office until his term ends in 2006. He did not address how he planned to put down the insurrection. His officials have said that, to prevent civilian casualties, any counterattacks must be part of a strategy that could take time to plan.

But the rebels who launched the revolt say they were armed by Aristide's party to terrorize his opponents in Gonaives (search), Haiti's fourth-largest city, which remained in rebel hands Thursday.

Winter Etienne, a leader of the rebel Gonaives Resistance Front (search), said Wednesday they were taking their battle to other cities.

"We already have a force hiding in St. Marc, and we also have one hiding in Cap-Haitien. They are awaiting the orders to attack," Etienne told The Associated Press, referring to towns on the western coast.

But it appeared police backed by pro-Aristide gunmen have reinforced their control in St. Marc, a key port city 45 miles west of the capital. In an indication most rebels had fled the city, insurgent leader Charles Nord Thompson on Thursday told RadioVision 2000 that he could account for only 10 of some 100 men who had seized the city Saturday.

On Wednesday, witnesses said, police entered the St. Marc slum stronghold where rebels were holed up, shooting to provide cover for Aristide militants who then set five houses ablaze and fired at fleeing residents.

Reporters saw the charred remains of one of two people witnesses said burned to death, and the bodies of three people apparently shot in the back.

Rebels perpetrated similar reprisals Wednesday in Gonaives, burning to death a man accused of being an Aristide hitman in the "necklacing" style: putting a tire over his head, dousing him with gasoline and setting him aflame.

It's a form of killing that Aristide once encouraged during the popular uprising that led to the downfall of the 29-year Duvalier family dictatorship in 1989 and his rise to power.

Haiti has suffered more than 30 coups in 200 years of independence, the last in 1991, when Aristide was ousted just months after his election as the Caribbean nation's first freely elected leader. President Clinton sent 20,000 U.S. troops in 1994 to end a military dictatorship, restore Aristide and halt an exodus of Haitian boat people.

U.S. officials say they now are on alert against any new exodus set off by the uprising.

"We are extremely concerned about the wave of violence spreading through Haiti," White House press secretary Scott McClellan said Wednesday. "We call on the government to respect the rights, especially human rights, of the citizens."

Aristide's popularity has waned since his party swept flawed 2000 legislative elections. International donors have frozen millions of aid dollars, and the president has been unable to keep his election promise of "peace of mind, peace in the belly."

In Haiti's second-largest city, the northern port of Cap-Haitien, Aristide militants manned fiery barricades to block any rebel incursion and fired shots through the night.

The house of a reporter for Radio Maxima (search), the voice of the opposition in Cap-Haitien, was burned, witnesses said. Radio Maxima was shut down Dec. 17 by police who smashed and shot up equipment.