For anyone curious as to why the use of cluster munitions is considered a war crime:

Because cluster bombs release many small bomblets over a wide area, they pose risks to civilians both during attacks and afterwards. Unexploded bomblets can kill or maim civilians and/or unintended targets long after a conflict has ended, and are costly to locate and remove. This failure rate ranges from 2 percent to 40 percent or more.

Cluster munitions are prohibited for those nations that ratified the Convention on Cluster Munitions, adopted in Dublin, Ireland, in May 2008. The Convention entered into force and became binding international law upon ratifying states on 1 August 2010, six months after being ratified by 30 states. As of 10 February 2022, a total of 123 states have joined the Convention, as 110 states parties and 13 signatories.