At least 12 soldiers have been killed and around 30 wounded since Sunday in a series of ambushes and explosions across the Sahel country, the army announced on state-run television on Wednesday.

"In order to face the recurrence of attacks in some localities in our country, the Council of Ministers has decided that security measures will be reinforced in military operation zones," the defence ministry wrote in a statement seen by AFP on Friday.

"Exceptional measures will be implemented to stifle this phenomenon," it added, without providing details.

It said the population should rest assured that the "situation is under control".

The West African nation has been grappling for years with attacks by armed groups linked to the Islamic State jihadist group and Al-Qaeda, and has also had to contend with unrest from Boko Haram militants.

The country has been led by military leaders since the July 2023 overthrow of its democratically elected president Mohamed Bazoum, who has since been held captive.

Around 1,500 civilians and soldiers in Niger have been killed in jihadist attacks over the past year, according to the Armed Conflict Location and Event Data project, an independent monitoring group.