A Russian drone attack caused significant damage to the radiation shelter of the Chernobyl nuclear power plant overnight, Ukrainian President Volodymyr Zelensky has said.
Chernobyl was the site of the world's worst civil nuclear catastrophe when one of its four reactors exploded in 1986.
That reactor is now enveloped by a protective shelter, known as a sarcophagus, to contain the lingering radiation.
The Russian drone struck the shelter of the destroyed power unit at the plant, causing a fire that has since been extinguished, he said.
"As of now, radiation levels have not increased and are being constantly monitored," Mr Zelensky said, adding that an initial assessment had found significant damage.
"The only country in the world that attacks such sites, occupies nuclear power plants, and wages war without any regard for the consequences is today's Russia," he said.
The International Atomic Energy Agency (IAEA) said an explosion was heard overnight and that fire safety personnel and vehicles responded within minutes and no casualties were reported.
"Radiation levels inside and outside remain normal and stable. IAEA continues monitoring the situation," the agency added.
Meanwhile, Russia accused Ukraine of carrying out an artillery attack on a thermal power plant it controls in southern Ukraine, which is located near the Zaporizhzhia nuclear power station.
Russian-installed local officials said the attack on the power plant in the city of Enerhodar had occurred late yesterday and had left more than 50,000 people without electricity.
Urgent work was under way to try to restore electricity supplies.
Russian news agencies cited a nuclear plant official assaying that the Zaporizhzhia nuclear power plant itself had not been damaged in the attack and was operating as usual.
