A massive attack by Russia against Ukraine's capital has killed four people and injured at least eight others, Kyiv Mayor Vitali Klitschko has said. Drones hit several regions overnight, including Zaporizhzhia, where at least 16 people, including three children, were injured, authorities said. Ukraine's foreign minister stated that hundreds of drones and missiles had been used in the latest attacks around Ukraine, while Russia has not commented. On the eve of the assault, Ukrainian President Volodymyr Zelensky warned that Russia's aggression would not stop with Ukraine, suggesting that Moscow is testing European air defenses through incursions into NATO countries. The attacks have initiated discussions about enhanced security measures in nearby nations, including Poland, where military jets were deployed in response to the crisis. Following the incidents, NATO has worked to bolster its eastern defenses, as tensions with Russia remain high.