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.

CHERNOBYL NUCLEAR POWER STATION, Ukraine (AP) — A drone armed with a warhead hit the protective outer shell of Ukraine’s Chernobyl nuclear plant early Friday, punching a hole in the structure and briefly starting a fire, in an attack Kyiv blamed on Russia. The Kremlin denied it was responsible.

Investigators from the Security Service of Ukraine (SSU) have opened a criminal case over Russia’s attack on the containment structure over the destroyed Unit No 4 at the Chornobyl Nuclear Power Plant (NPP).