"In the area of Mehana, terrorist elements perpetrated several heinous acts of violence against the defenceless civilians, with a heavy and tragic toll," it said, citing 14 casualties on an unspecified date, which followed the death of at least one other civilian Tuesday in the same region.

Mehana was among six areas targeted in Niger's Tillaberi region, which borders Mali and Burkina Faso and has become a hideout for jihadists affiliated with the Islamic State and Al-Qaeda.

Civilians in Mehana are frequently targeted by the jihadists, leading to massive displacement.

Also in the Tillaberi region on Tuesday, one civilian was killed and three others wounded in a "violent clash" between an army reconnaissance unit and "terrorists" near the town of Chatoumane, the army said.

"The security forces reacted effectively, neutralising several terrorists," it said.

Niger is ruled by military leaders who seized power in a July coup, citing a worsening security situation as justification for the power grab.

Niamey also faces violence by Boko Haram jihadists and their rivals Islamic State West Africa Province from the southeastern region of Diffa near Nigeria.

According to Acled, which tracks conflict, jihadists have killed about 1,500 civilians and soldiers in the past year in Niger, compared with 650 in the year to July 2023.