Haitians erected fiery barricades and tried to storm the National Palace on Tuesday as protests against rising food prices, which have killed five people, paralyzed the impoverished nation's capital.

Some demonstrators in the city carried empty plates to show the government they had nothing to eat.

U.N. peacekeepers fired rubber bullets and tear gas to control the angry mob after the protesters used large steel garbage containers as battering rams to try to smash the gates of the palace in downtown Port-au-Prince, witnesses said.

Several people were injured by rubber bullets, including two local journalists, the witnesses said, adding that troops swarmed the area in armoured personnel carriers and trucks, clearing out the demonstrators.

"If the government cannot lower the cost of living it simply has to leave," said protester Renand Alexandre. "If the police and U.N. troops want to shoot at us, that's OK, because in the end if we are not killed by bullets we'll die of hunger."

Public safety chief Eucher Luc Joseph appeared on national TV to warn that only peaceful protests would be allowed.

"We won't tolerate people who are threatening people's lives," he said. "The security forces will act vigorously."

Businesses were shuttered, schools were closed and many residents stayed inside as the demonstrations that began last Wednesday in the southern city of Les Cayes gripped the teeming capital of the Caribbean nation of nearly 9 million people.

Five people have been killed in a week of protests against high food prices and rising living costs in the poorest country in the Americas.

A man died in gunfire on Monday and four others were killed during a riot last week in Les Cayes, when an angry mob looted a food warehouse and U.N. peacekeepers were attacked.

In response to the unrest, the government of President Rene Preval, whose 2006 election brought a measure of calm to a Caribbean nation roiled by decades of political upheaval, announced a multimillion-dollar package of economic investments aimed at lowering the cost of living. The growing violence is the worst since Preval took office.

CALL FOR EMERGENCY AID

The U.N. Security Council deplored the violence and called for emergency aid to relieve hardship in a nation where 80 percent of the people live on less than $2 a day.

Authorities have accused drug dealers and smugglers of using the food protests to stir up trouble. Haitian National Police Chief Mario Andresol said "so-called demonstrators" were looting private businesses in the capital.

"When you have people who have tried to force their way inside the presidential palace, this is not peaceful and we are not going to tolerate the violence," he said.

Thousands of protesters poured into the streets of the capital on Tuesday afternoon, waving tree branches, pounding on drums and chanting "down with the government" and "down with hunger." Others defied police attempts to clear clogged roadways by dragging wrecked cars and other debris into intersections and setting fire to piles of tires.

Residents say the prices of rice, corn, beans, cooking oil and other staples are skyrocketing. The cost of rice and some other commodities has virtually doubled in six months.

"Everything is so expensive, I think it is a plot between the government, the business leaders and the international community against the people," protester Michel Presendieu said. "Don't you see MINUSTAH (UN troops) shooting at the hungry people? And the government is not saying anything."

U.N. troops were sent to Haiti in 2004 following the ouster of then-president Jean-Bertrand Aristide in a bloody rebellion. The United Nations Stabilization Mission in Haiti (MINUSTAH) has nearly 9,000 Brazilian-led soldiers and civilian police providing security.