At least 10 members of Haitian armed gangs have been killed and nearly 20 others wounded in clashes with UN troops and Haitian police, according to UN officials.
The clashes took place on Friday in Cite Soleil, a sprawling slum suburb of the Haitian capital known as a stronghold of supporters of former president Jean Bertrand Aristide.
"The incidents occurred during a joint operation undertaken by the UN force together with Haitian police in order to restore security in the neighbourhood," a UN officer said. "Our force was met in the neighbourhood with gunfire."
Cite Soleil is home to about 350,000 people.
Two Haitian police officers were wounded during the operation, which involved a Jordanian battalion deployed in the country as part of the UN mission and about 60 Haitian police officers.
A UN soldier from the Philippines was shot in the head and killed in Cite Soleil on Thursday.
The Filipino was the third UN soldier killed over a one-month period. Soldiers from Sri Lanka and Nepal were killed in March. The UN force was deployed to Haiti last year, after Aristide fled amid an armed uprising.