Cluster bombs were used for the first time by Mali’s army and its Russian allies in northern Mali, with the weapons dropped at least twice last week during anti-terror operations, according to images obtained by Bellingcat. The first strike happened last Friday at Oubder near In-Gouzma in the Timbuktu region, and a second strike followed on Sunday at Tadjmart near Aguelhoc in the Kidal region.

Specialists who examined the images identified a Russian-made RBK-500 cluster bomb and ShOAB-0.5 bomblets, the type of small submunitions that can scatter across a wide area after release. The details matter because more than 100 countries have signed the Convention on Cluster Munitions, and Mali ratified the treaty after it came into force in 2010.

Cluster munitions are designed to release many smaller explosives over a wide area, and many fail to detonate immediately, leaving lethal remnants behind long after fighting ends. The Landmine and Cluster Munition Monitor says more than 90 percent of people killed or wounded by cluster bombs worldwide are civilians, a toll that has helped drive the long-standing effort to ban them.

The strikes also land in a conflict zone where jihadist groups, separatist movements and the army have been fighting in northern Mali for more than a decade. That makes any use of the weapons especially fraught, because the battlefield is already crowded, mobile and difficult to verify from the ground.

For Mali, the issue is not just military. It is legal and political too. A state that has signed on to a global ban is now facing evidence that its forces, alongside Russian allies, may have used one of the world’s most controversial weapons in an active war zone. The next question is whether the strikes will be acknowledged, denied or investigated, and whether the images now circulating are enough to force a reckoning.