In Gao, a city still held by militants, the charity Action Contre la Faim said it had found cases of acute malnutrition, Radio France Internationale reported Friday.
Militants are forcing people fleeing the fighting to give up their food, valuables and vehicles, the United Nations refugee agency UNHCR said.
Since French forces began bombing the insurgents Jan. 11, more than 9,000 people have fled to neighboring countries, UNHCR said. Some 150,000 refugees are living outside Mali, the agency said, with 230,000 others internally displaced.
In Timbuktu, militants fleeing the city are blamed for destroying utilities, leaving the city without electricity, water or telephone service, CNN reported.
Moussa Ag Assarid, a spokesman for the Tuareg separatist party MLNA, said in Paris most of the "terrorists" fled Mali's historic cultural center after French planes bombed the militants' headquarters Tuesday.