"But there are also serious allegations that pro-Russian rebel forces, and possibly Russia itself, have used cluster munitions in eastern Ukraine.
All parties to the conflict in Eastern Ukraine have access to the same weapons, so it is not always possible to draw definitive conclusions with respect to specific attacks.
Our on-the-ground investigation established that, given the incoming direction, these cluster munitions could have been fired by either Ukrainian or Russian forces.
While circumstances raised the possibility of Russian or pro-Russian rebel responsibility, we ultimately made no definitive attribution of responsibility for this attack. "