Seven soldiers and four back-up troops have been killed in two ambushes in Burkina Faso’s troubled north, the army said.

The first attack near the town of Solle on Thursday led to the deaths of two soldiers and four civilians helping the army while five paramilitary troops perished in another raid the same day at Ouanobe, the army said in a statement received Friday.

The ambushes were staged by “terrorists,” according to the army.

Nine people were wounded, it said, adding that the bodies of some 20 attackers had been found during clean-up operations.

Weapons, ammunition, transport and communication equipment were also found and had been either seized or destroyed.

Extremist groups affiliated with al-Qaeda and ISIS have regularly carried out attacks in northern and eastern Burkina Faso since 2015, killing more than 2,000 people and displacing almost two million.

Unrest linked to terrorist groups also plagues Burkina Faso’s West African neighbors Mali and Niger.