Port-au-Prince, Nov 22 (DPA) An estimated 1,250 people have died from cholera and an additional 21,000 have been sickened by the disease, Haiti's health ministry said.

Nearly half of the deaths -- 673 -- from cholera, which is contracted through contaminated water and causes severe diarrhoea and vomiting, were reported in the lower Artibonite region, north of capital Port-au-Prince, where the outbreak was first reported Oct 19.

An estimated 63 deaths have been reported so far in Port-au-Prince, the ministry said Sunday.

The UN anticipates that up to 200,000 people will show symptoms of cholera, ranging from cases of mild diarrhoea to severe dehydration.

While the Haitian government immediately declared a public health emergency and non-governmental organisations have been working to increase access to prevention and treatment measures, the course the epidemic takes is difficult to predict, US health experts have said.

Tensions grew last week because of the epidemic, with demonstrators throwing stones at UN soldiers guarding the presidential palace.

Haitian police used tear gas to disperse the agitated crowd in front of the palace, which is surrounded by hundreds of makeshift camps housing the homeless from the Jan 12 earthquake that levelled much of the capital, killing an estimated 230,000 people.

Four people were killed in clashes through the week in northern Cap Haitien, Haiti's second-largest city.