U.N. peacekeeping troops working with Haitian police have traded heavy gunfire with gangs in a slum of the capital, Port-au-Prince.

Officials say at least nine people were killed Friday and several others were wounded during the early morning raid in the volatile slum of Cite Soleil. All the casualties were believed to be civilians.

The U.N. force said it launched the operation with Haiti's national police to stop a surge in kidnappings and other crimes by gangs in the slum.

U.N. peacekeepers have been in Haiti since the ouster of former President Jean-Bertrand Aristide in February 2004.

Haiti is the Western Hemisphere's poorest country and has been plagued by civil and political violence. Earlier this year, international donors pledged $750 million to improve basic services and revive the economy in Haiti.

Some information for this report provided by AP, AFP and Reuters.