UN troops fired tear gas to disperse demonstrators throwing stones and blocking roads in Cap Haitien.

Some Haitians have accused peacekeepers from Nepal of introducing cholera to Haiti for the first time in a century.

The UN says it has found no evidence to justify the accusation, but the cholera strain has been matched to South Asia.

The UN humanitarian co-ordinator for Haiti, Nigel Fisher, said the demonstrations showed the cholera outbreak had gone beyond a health crisis to become "an issue of national security".

Hundreds of protesters threw stones at UN peacekeepers, set up burning barricades and torched a police station in Cap Haitien, Haiti's second city.

Unconfirmed reports said shots were fired during the clashes, and at least 10 people were injured.

As well as calling for UN peacekeepers to leave Haiti, demonstrators accused the government of "leaving the people to die", the AFP news agency reported.

Protesters also clashed with UN troops from Nepal in the central town of Hinche.

Aid agencies are battling to contain the disease in the capital Port-au-Prince, amid fears it will spread through camps housing 1.1m earthquake survivors.

The UN has appealed for US$164 million to tackle the epidemic over the next year.The worst affected area remains the central province of Artibonite, where at least 595 people have died.