UN peacekeepers in Haiti have struggled for a second day to control protests by supporters of deposed President Jean-Bertrand Aristide.
UN troops are finding it hard to co-ordinate the relief effort
Shops in the capital Port-au-Prince closed as armed Aristide loyalists smashed cars and set up roadblocks.
Interim Prime Minister Gerard Latortue said local police had killed several Aristide supporters, but he gave no further details.
Earlier, the UN appealed for nearly $60m for victims of recent storms.
The UN says the security situation in Haiti is making it harder to co-ordinate the relief effort.
As well as controlling Port-au-Prince, the UN is facing a challenge from looters and armed gangs in the city worst affected by the floods, Gonaives.
Hurricane Jeanne, which hit Haiti last month, killed more than 1,500 people and left 200,000 starving and homeless.
'A lot of shooting'
Gunfire broke out on Thursday as Mr Aristide's loyalists emerged from the slums, promising that he would return from exile in South Africa.
They were marking the 13th anniversary of his being ousted from power in 1991 by Haiti's army.
On Friday, protesters in the western Martissant suburb fired
shots in the air, blocked roads with piles of
burning tyres and smashed car windows, witnesses said.
"All of a sudden there was a lot of shooting, but no-one
saw who did it," shoeshine man Jonel St Louis told the Associated Press news agency.
Mr Latortue vowed to capture those responsible for the violence, in which some civilians were also reportedly hurt.
UN peacekeeping forces say they turned away about 150 armed men who tried to enter Gonaives on Wednesday.
Witnesses say the men, said to be former Haitian soldiers, told UN troops they wanted to take food to those residents affected by the storm.
The men accused the UN mission of not doing enough to protect local people, and some said they would try to enter the city again.
The UN says it needs a 1,000 more peacekeepers to help to protect food convoys heading for Gonaives.
More than 1,500 are known to have died in the port city while about 900 are missing, many of them possibly washed out to sea during the storm nearly two weeks ago.
A lack of clean drinking water is adding to the food crisis in Gonaives.
Volunteer doctors have spoken of appalling conditions as they try to help the storm survivors in makeshift clinics.
Amputations have been carried out under primitive conditions, many people have infected wounds, and there are widespread cases of diarrhoea.