Kyiv, Jun 26:  Russian air defences intercepted 660 Ukrainian drones in a major nighttime attack on 12 Russian regions as well as the Russia-held Crimean peninsula, the Black Sea and the Azov Sea, Russia's Defence Ministry said Friday. It appeared to be one of the biggest drone attacks on Russia and the illegally annexed Crimea since Russia's full-scale invasion of Ukraine more than four years ago. The previous biggest Ukrainian attack over the past year was 556 drones on May 17.