Police attacked rebels holed up in a slum in the port city of St. Marc (search) on Wednesday and gunmen loyal to President Jean-Bertrand Aristide (search) torched homes, killing two people as looting and reprisals raged in a popular revolt that has left at least 45 dead.

Outside Gonaives, where the uprising began last Thursday, witnesses said people "necklaced" a man accused of being an Aristide spy. "They put tires on him, poured gasoline and burned him," 17-year-old Patricia Joseph told a reporter. "Everyone stood up and said it was good."

With the Haitian government locked in a deadly battle with opponents, the White House on Wednesday issued a rebuke of Aristide's government.

"We are extremely concerned about the wave of violence spreading through Haiti. And we certainly deeply regret the loss of life," said Scott McClellan (search), press secretary to President Bush. "We call on the government to respect the rights, especially human rights, of the citizens and residents of Haiti."

Haiti has suffered increasing violence since Aristide's party swept flawed legislative elections in 2000 and international donors blocked millions in aid. Opponents say they will not take part in new elections unless Aristide resigns.

In St. Marc, an important port 45 miles west of Port-au-Prince, gunmen loyal to Aristide shot up a southern neighborhood before dawn Wednesday and torched three houses, witnesses told The Associated Press. They said two people were killed; it was unclear whether they died in the blaze or in the shooting.

Government opponents burned down a clinic because officials refused to hand over two wounded anti-government militants, Radio Vision 2000 reported. It said Aristide militants seeking revenge then set an opposition radio station ablaze.

In the northern port of Cap-Haitien, sporadic gunshots crackled overnight and attackers looted a food warehouse, taking advantage of a blackout because the city has run out of fuel for generators.

Aristide supporters set up blazing barricades, blocking the city for a second day against a possible rebel incursion.

"We're going to devour them," Jean-Claude Joseph, 35, said at a roadblock.

In Gonaives, rebels controlled crowds fighting over dwindling gasoline supplies.

"Get in line. Don't push!" shouted three rebels who held their rifles high in the air in warning. People obeyed.

"I've been here since 6 o'clock," Antrecil Petithomme, in her 60s, complained in the crowd hoping to fill jerry cans.

"I want to resell it and try to buy some flour to make food," she said, explaining food prices have multiplied since rebels and citizens supporting them have blocked roads with massive barricades against a possible counterattack by police.

But no police were seen near the city 60 miles from Port-au-Prince, and government officials indicated that, to prevent civilian casualties, any counterattack might take time.

"To avoid the suffering and involvement of the civilian population, we have to implement a strategy," Gerard Dubreuille, undersecretary for public security, said Tuesday. "Our reaction may be slow, it will be efficient."

Police have retaken three of 11 towns in northern and western Haiti.

Radio reports said gunmen had torched two northern police stations on Monday, forcing police to flee from Limbe and Bassin Bleu. Police stations are a major target of the revolt, which the government calls a coup attempt, because officers are accused of siding with government supporters in increasingly violent protests that began mid-September.

In St. Marc, a city of about 100,000 people, witnesses said police were firing at rebels holed up in a midtown slum.

Rebels seized the city Sunday, and hundreds of residents looted shipping containers.

On Monday, after sporadic gunbattles, police reoccupied the town.

The Haitian Red Cross and the International Committee of the Red Cross said they were having difficulty evacuating wounded people and supplying hospitals, and complained armed people were breaking into hospitals.

"Each day wounded people in dire need of medical care are being rushed to hospitals," said a statement.

The World Health Organization said a food crisis is looming because roadblocks are preventing deliveries to 268,000 people in the north dependent on food aid.

Dozens of barricades, made up of burned-out trucks, commandeered cars, boulders, felled trees and blazing tires set atop heaps of garbage, have blocked the road to northern Haiti, particularly at Gonaives.

The Democratic Platform opposition coalition said it was trying to get government permission for a peaceful demonstration in Port-au-Prince on Thursday. The coalition has distanced itself from the bloody uprising, led by a gang formerly allied with Aristide and former soldiers who helped oust him in a 1991 coup.