Brazilian UN peacekeepers kept the protesters back from the palace
Crowds of demonstrators in Haiti have tried to storm the presidential palace in the capital Port-au-Prince as protests continue over food prices.
Witnesses say the protesters used metal bins to try to smash down the palace gates before UN troops fired rubber bullets and tear gas to disperse them.
Several people are reported to have been injured in the clashes.
At least five people have been killed in Haiti since the unrest began last week in the southern city of Les Cayes.
The demonstrators outside the presidential palace said the rising cost of living in Haiti meant they were struggling to feed themselves.
"We are hungry," they shouted before attempting to smash open the palace gates.
In recent months, it has become common among Haiti's poor to use the expression "grangou klowox" or "eating bleach", to describe the daily hunger pains people face, because of the burning feeling in their stomachs.
'Gasoline and matches'
The protesters demanded the resignation of President Rene Preval, who came to power two years ago promising to restore peace to a country torn apart by fighting between rival armed gangs.
Protesters ran for cover as shots rang out near the palace
Mr Preval is believed to have been inside the palace at the time.
"I compare this situation to having a bucket full of gasoline and having some people around with a box of matches," Preval adviser Patrick Elie was quoted as saying by The Associated Press.
"As long as the two have a possibility to meet, you're going to have trouble."
Rising food prices are causing unrest around the globe but in Haiti, one of the poorest countries in the world, the protests threaten to destabilise an already fragile democracy.
UN envoy Hedi Annabi, who briefed the Security Council in New York on Tuesday, said Haiti's progress was "extremely fragile, highly reversible, and made even more fragile by the current socio-economic environment".
Violence in Haiti has often been linked to poverty with more than half the population surviving on less than a dollar a day.
Critics say both Mr Preval and the international community have focused too much on political stability and not enough on helping to alleviate poverty and now growing hunger.
The protesters are also focusing their anger on the 9,000 or so UN peacekeepers sent to Haiti in 2004.
Their mission was to quell the chaos that followed the ousting of former President Jean-Bertrand Aristide, the country's first democratically elected leader.
Are you in Haiti? Did you witness the clashes? Have you been affected by rising food prices?
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