Between 700 and 800 African troops from Benin, Nigeria, Togo and Burkina Faso have arrived in Mali, according to U.S. State Department spokeswoman Victoria Nuland. Senegalese troops and up to 2,000 from Chad are on the way, she said.
Journalists are still barred from traveling into northern Mali, which has been under the control of militant Islamists for several months.
But the CNN crew was able to enter Diabaly on Monday, where it was told by Malian and French forces that Islamists left after they were hit directly in one of their makeshift camps by the French and Malians.
The scene after one battle included burned-out armored vehicles and a truck that at one point belonged to the Islamists.
A Malian officer, Col. Seydou Sogoba, told CNN that the Islamists were using sophisticated weapons like he had never seen before. He believes they originated in Libya.
As the news crew drove into town, the dusty streets in the extremely poor area were mostly empty except for military vehicles and French and Malian troops. Whatever trucks had belonged to the Islamist rebels were bombed and burned out. Destroyed high-caliber weapons were seen in the vehicles.
A French colonel, exhausted from fighting and who wished not to be named, told CNN that foreign fighters -- including some who are Algerian -- had been pushed out of the area.
Sogoba told CNN the fight against the rebels was very hard, but he is focused on "preserving the national integrity" of Mali.
French President Francois Hollande has said that if his country had not intervened, Mali "probably would have fallen into the hands of terrorists."
French involvement began the day after militants said January 10 that they had seized the city of Konna, east of Diabaly in central Mali, and were poised to advance south toward Bamako.
Ethnic Tuaregs who had returned to Mali well-armed from fighting for late Libyan leader Moammar Gadhafi staged a military coup last year against the Malian government. Islamic extremists capitalized on the chaos, carved out a large haven in Mali's north and imposed a strict interpretation of Sharia law. The Islamists banned music, smoking, drinking and watching sports on television. They also destroyed historic tombs and shrines.
Those events stoked fear among global security experts that Mali could become a new hub for terrorism.
Meanwhile, the Norwegian Internal Displacement Monitoring Centre warned that the humanitarian crisis in Mali is worsening.
Because Algeria has closed its borders, people in the north are increasingly heading to the desert, where they will face harsh conditions and struggles over food and water with limited humanitarian assistance, the group said.
"They cannot stay where they are due to the grave insecurity caused by the conflict," said Sebastian Albuja, head of the center's Africa and Americas Department. "Yet the meager resources and the diminished coping abilities of the government and humanitarian actors means that they are faced with limited options."
Many are fleeing on foot because they can't afford boats or buses, Albuja said, and even if they do make it, they get there only to find the roads blocked.
The violence could soon displace up to 700,000 in the country and around the region, said Melissa Fleming, a spokeswoman for the United Nations' refugee agency.