Ttwin attacks were carried out on Thursday in Bourzanga district, a security source and an official with the VDP auxiliary force said.
The VDP source said that in the latest attack, six militiamen were killed at the village of Alga and three at Boulounga, adding that "several attackers were also killed."
On Wednesday, the army admitted that civilians had killed during an air strike in the east.
It gave no toll, but local inhabitants told AFP that about 30 people, most of them women who had gone to attend ceremonies to inaugurate a mill, had died.
On June 11, 86 people were massacred at Seytenga in the northwest, in one of the bloodiest acts of the long-running insurgency.
Thirty-four villagers were killed on July 2 and 3 in the north and northwest.
The landlocked Sahel state is wrestling with a seven-year-old jihadist insurgency that has claimed thousands of lives and driven some two million people from their homes.
More than 40 percent of the country is no longer under government control, according to official figures.
The Seytenga attack prompted the authorities to set up two "zones of military interest" in the worst-hit regions of the north and east.
The idea is to have zones that are banned for civilians, giving the armed forces freer range to attack jihadists.