BRUSSELS - The evidence points to the use of chemical weapons by Syrian President Bashar Assad's forces against a besieged rebel-held town in Syria, the European Union said on Sunday, calling for an international response."The evidence points towards yet another chemical attack by the regime," the EU said in a statement. "It is a matter of grave concern that chemical weapons continue to be used, especially on civilians. The European Union condemns in the strongest terms the use of chemical weapons and calls for an immediate response by the international community."The bloc called on the UN Security Council to re-establish its checks to identify perpetrators of chemical attacks and on Russia and Iran to use their influence with Assad to prevent further attacks.The Syrian state denied government forces had launched any chemical attack in the town of Douma.