At least seven mercenaries from Russia’s Wagner private military contractor group were killed in an attack in central Mali that was claimed by an affiliate of al Qaeda in North Africa, Site Intelligence group said Friday.

Wagner previously suffered heavy losses in a July battle with predominantly Tuareg rebels and Islamists near Mali’s border with Algeria which exposed the dangers faced by mercenaries working for military juntas in West Africa's Sahel region.

Mali and its neighbours Burkina Faso and Niger are struggling to contain separatists and powerful offshoots of Islamic State and Al Qaeda who have occupied swathes of territory in the Sahel over the past 12 years.

SITE Intelligence group, which monitors extremist activities in the region, said in a statement that al Qaeda affiliate JNIM claimed responsibility for the attack, which took place on Thursday.

JNIM killed seven Russian Wagner mercenaries and seized some weapons, SITE said.

A video seen by Reuters showed bodies of at least five white men in army fatigues lying around a military vehicle following an attack. Reuters was not able to verify the video’s authenticity.

Photos shared by SITE Intelligence purportedly from JNIM showed bloodied, lifeless bodies of soldiers and several boxes of arms and ammunition.

A spokesperson for the Malian army could not be reached for comment.

A Malian army source said he saw seven dead bodies including Russian fighters, while two local administrators confirmed the attack. One of them said five Wagner fighters were killed.

A consultant working on security in the region said the attack was carried out by Katiba Macina, a branch of JNIM, and that at least six Russians had been killed.

The consultant said the Russians were Africa Corps fighters, referring to a Kremlin-controlled paramilitary force that has replaced Wagner in Africa over the past year.

Mali has previously said Russian forces there are not mercenaries but trainers helping local troops with equipment bought from Russia.