A significant threat to Ukrainian cities has been identified, with the potential to strike with little to no warning. This threat is related to Russia's exploitation of a key vulnerability in Ukraine's defenses. Ukraine has recently been on the offensive against Russia, affecting its oil refining capabilities and causing disruptions.

However, Russia has found a way to counterattack, targeting Ukrainian cities with high-speed missile attacks. Further details on this situation are available from the source, including information on recent attacks in the region of Ukraine's capital. The source provides more context on the ongoing conflict between Russia and Ukraine.