PORT-AU-PRINCE, Haiti (AP):

An aggressive new United Nations offensive has prompted several Haitian gang members to flee their slum strongholds and cross the border into the Dominican Republic, the top official of the international body in Haiti said Thursday.

Edmond Mulet, the United Nations special envoy to Haiti, said Dominican authorities have captured several of the gang members crossing into their territory since the U.N. peacekeepers launched a series of crackdowns on gangs in two Port-au-Prince slums earlier this month.

"We heard from the Dominican authorities ... that they have arrested several gang members or people trying to flee to the Dominican Republic," Mulet told the Associated Press. "This is normal, especially if you are a gang member and have money, just to leave the country to go somewhere where you will not be known."

Officials in the Dominican Republic - which shares the Caribbean island of Hispaniola with Haiti - did not immediately return phone calls seeking comment.

U.N. troops and Haitian police raided the Martissant slum last weekend and arrested 31 gang members. On Friday, more than 700 troops raided another slum, Cite Soleil, and killed one suspected gang member and wounded four others.

The U.N. Security Council on Thursday voted unanimously to extend the peacekeeping mission for eight months following an agreement between the United States and China on the length of the new mandate.