UN Secretary-General Ban Ki-moon has warned that the use of cluster bombs in Yemen by the Saudi-led coalition may amount to war crimes. Ban said he had received “troubling reports” of cluster bomb attacks on January 6 on the rebel-held capital Sanaa. The UN Chief said in a statement, the use of cluster munitions in populated areas may amount to a war crime due to their indiscriminate nature. Cluster bombs are banned under a 2008 International Convention, although Saudi Arabia and the United States are not signatories. The office of the UN High Commissioner for Human Rights said on Tuesday that its staff in Yemen had found remnants of 29 cluster bombs during a field visit in Haradh district in the northwest.