Port-au-Prince, Haiti ? A gunbattle broke out between U.N. peacekeepers and supporters of ousted Haitian President Jean-Bertrand Aristide on Saturday, wounding a peacekeeper for the first time in the force’s 4-month-old mission.

The clashes, which Haitian police said also left one officer wounded, came as protesters in the northwestern city of Gonaives crowded outside a Mass for flood victims accusing Haiti’s interim president and prime minister — who were attending — of not doing enough to help hungry survivors three weeks after Tropical Storm Jeanne.

Heavy gunfire erupted in the capital of Port-au-Prince after about 150 Brazilian troops using armored vehicles and 150 Haitian police in trucks rolled into the volatile slum of Bel Air, where armed young men have been demanding the return of Aristide from exile, Brazilian Lt. Col. Ezequiel Izaias said.

The Brazilian soldier was wounded in the foot — the first casualty among some 3,000 peacekeepers, Kongo-Doudou said. He also said it appeared some of the gunmen were wounded, but it was unclear how many.

Kongo-Doudou said troops and police arrested more than 60 people suspected of attacking them. Police were seen detaining some men, holding them to the ground at gunpoint and tying their hands with rope.

An estimated 200,000 people are homeless in Gonaives, many living on sidewalks and rooftops.

The storm unleashed floods and mudslides that killed at least 1,870 and left some 884 missing, most presumed dead.