French special forces intervened at an army base in the west African country of Niger after Islamists staged a car bombing and then attacked the base, Defence Minister Jean-Yves Le Drian said Friday.
"The situation has stabilised as we speak, especially in Agadez, where our special forces intervened to back the Niger forces," he said on France's BFMTV.
A defence ministry source said two "terrorists" had been killed in the French offensive, which took place at dawn on Friday.
Thursday's twin bombings in Niger, which also targeted uranium mine in northern Arlit that is majority-owned by France's Areva, have claimed at least 20 lives.
The "Signatories in Blood" jihadist group led by Algerian Mokhtar Belmokhtar claimed responsibility and threatened more attacks on France and countries involved militarily in battling Islamist extremists in neighbouring Mali.