Firefighters worked across the weekend to tackle smouldering roof insulation in the giant protective shelter which covers Chernobyl's unit 4 following the drone strike on Friday. Radiation levels in the area remain normal - the original protective shelter inside the giant structure did not suffer any damage.

Ukraine’s nuclear ghosts have been stirred up again after a drone armed with a warhead hit the protective outer shell of the plant at Chernobyl, the site of the world’s worst nuclear accident.