(AP) -- Protesters threw rocks at a cholera treatment center as it was preparing to open in the city of St. Marc on Tuesday, highlighting the fear surrounding a disease that was almost unknown in Haiti before it began spreading through the countryside, aid workers said.
Some of the roughly 300 students and other protesters said they feared the Doctors Without Borders-Spain clinic would bring more of the disease to their seaside town, which is one of the hardest hit in the week-old epidemic that has killed 284 people and infected 3,769, according to United Nations figures.
U.N. peacekeepers from Argentina arrived with riot shields to reinforce police. Warning shots were heard; the U.N. said its soldiers fired blanks. There were no reports of injuries.
Haitian health officials assured the crowd the clinic would not open in that neighborhood. Doctors Without Borders-Spain country chief Francisco Otero said the medical aid group would try to reopen it in another part of St. Marc. The clinic is intended to rehydrate and treat people with the severe diarrheal disease.
"In the coming days we are going to start to work with this community, to explain that there is no risk for them to have such a facility," Otero told The Associated Press.
More than 420 new cholera cases were confirmed Tuesday, according to the U.N. Office for the Coordination of Humanitarian Affairs. Twenty-five new deaths were confirmed, bringing the total to 284.
OCHA spokeswoman Imogen Wall says the majority of cases occurred along the central Artibonite River with many new instances in Haiti's central plateau. St. Marc's main hospital was the first to widely alert the epidemic as it overflowed with the sick and dying.
U.N. staff have been told to avoid areas of heavy infection unless they are given special permission to go there. Guatemalan police manned a checkpoint Tuesday on the highway from Port-au-Prince to Mirebalais, a hard-hit city in central Haiti, to make sure unauthorized U.N. vehicles did not pass.
Aid workers, meanwhile, scrambled to contain the spread of the disease, which has not occurred in Haiti for generations.
Speaker trucks passed through neighborhoods in the capital, where a handful of cases have been confirmed in people who apparently contracted it in the countryside, advising the city's millions of residents to wash their hands.
The Dominican Republic, which borders the central plateau where many new cases are being found, announced that all people crossing the border must wash hands and complete a medical form. They also stepped up military surveillance and closed a twice-weekly binational market on Monday, sparking protests on the Haitian side of the border.
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