On Saturday, the armed men attacked Tchombangou and Zaroumdareye villages near the Malian border in southwestern Niger.
At least 100 civilians lost their lives and 75 others injured in the attacks, Interior Minister Alkache Alhada said.
It was one of the deadliest days in living memory in the country, which has been grappling with ethnic violence for decades.
Initially, Niger’s officials announced 56 fatalities among civilians, adding that the incident also left 20 injured.
No group has claimed responsibility for the attacks.
Niger’s Tillabéri region is badly affected by the insurgency in the Maghreb. Major attacks occurred in January 2020, May 2020, August 2020 and January 2021.