(CNN) -- The World Food Programme on Monday appealed to the international community for money to support its operations in Haiti, where at least four people have died during two days of rioting over the price of food.

"Riots in Haiti underline the additional need for lifesaving food assistance," said WFP Executive Director Josette Sheeran in a written statement. "At this critical time, we need to stand with the people of Haiti and other countries hardest hit by rising food prices."

Thousands of demonstrators on Monday marched through the streets of Haiti's capital, Port au Prince. Their dissatisfaction was underscored by piles of tires belching thick black smoke into the air.

Several stores were raided and looted and some cars were torched, said Samuel Madistin, a lawyer in Port-au-Prince.

"We're hungry, there are no jobs," said Joseph Orange, an out-of-work translator in Port au Prince. "It's really a problem."

"The cost of living is kind of high, and people don't have any purchasing power," said Georges Brunet, a professor of economics in the capital, where students made up many of the demonstrators. "They are university students with no future," he said. "They are hoping to get some revenues to make ends meet.

"Maybe the government will wake up and start making some long-lasting commitments to people," he added.

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On Friday, the United Nations peacekeeping mission in Haiti said the situation was tense in the southwestern town of Les Cayes a day after demonstrations over the rising cost of living there led to an attack against the U.N. office.

Protesters broke into the U.N. compound, ignored warning shots and stole from two containers, the mission reported.

They burned shops, threw rocks and fired weapons at some of the U.N. workers, though none of the U.N. workers were injured.

A report by the secretary-general on the U.N. stabilization mission in Haiti, written March 26 and delivered Monday to the U.N. Security Council, noted that Haitians' hardship had been exacerbated by recent price hikes and said, "The political situation remains fragile."

The U.N. food agency first appealed last month for $500 million to help offset an estimated 55 percent increase in the price of food and fuel since last June.

Unrest linked to the cost of food and fuel has occurred not only in Haiti -- the poorest country in the western hemisphere's --but in Burkina Faso, Cameroon, Egypt, Indonesia, Ivory Coast, Mauritania, Mozambique and Senegal, according to the program.

Malnutrition is particularly acute in Haiti, where the average Haitian diet contains just 1,640 calories, 460 calories short of the typical 2,100 daily requirement, the agency said.

WFP said it has received only 13 percent ($12.4 million) of the $96 million it needs to help 1.7 million people in Haiti.

"What we see in Haiti is what we're seeing in many of our operations around the world -- rising prices that mean less food for the hungry," said WFP's Sheeran. "A new face of hunger is emerging: even where food is available on the shelves, there are now more and more people who simply cannot afford it."

Eighty percent of the 8.7 million Haitians live in poverty and 54 percent live in abject poverty, according to the CIA's World Factbook. E-mail to a friend

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