STORY: A tolling bell in northern Ukraine began a series of ceremonies marking 40 years since the deadly Chornobyl nuclear meltdown.
The anniversary on Sunday came amid lingering fears that Russia's ongoing war could spark a repeat of the world's worst nuclear disaster.
Millions were exposed to radiation, hundreds of thousands forced to flee, and large stretches of land contaminated after an accidental explosion at the Soviet-built plant on April 26, 1986.
In Kyiv, Ukrainian officials and so-called 'liquidators' gathered at a memorial.
Hundreds of thousands of liquidators were sent in to the nuclear plant to clean up after the blast, as Soviet authorities tried to hide the scale of the disaster.
One of them, Serhii Balashov, said Soviet officials also refused to acknowledge links between the cleaners' illnesses and them cleaning up in Chornobyl.
Thirty-one plant workers and firemen died in the immediate aftermath, mostly from acute radiation sickness.
Thousands of others have since succumbed to radiation-related illnesses such as cancer, although the total death toll and long-term health effects remain a subject of intense debate.
Marking the disaster, which spewed radioactive material across much of Europe, has taken on sharp new meaning as Russia invades its smaller neighbor.
Kyiv says Moscow has repeatedly sent missiles and drones near the plant during attacks on Ukrainian cities.
A Russian drone strike damaged a critical protective shield in February last year, officials said.
The steel and concrete arc was installed with international effort in 2016 to shield the original sarcophagus hurriedly built in 1986 to cover tons of radioactive debris.
No leaks were detected, but more than $580 million worth of repairs are needed, according to the European Bank for Reconstruction and Development.
After meeting Ukraine's energy minister on Sunday, International Atomic Energy Agency chief Rafael Grossi said repairs need to start as soon as possible.
"Leaving the situation as is now is problematic."
::August 2022
Control of the Russian-occupied Zaporizhzhia Nuclear Power Plant is also a major sticking point in U.S.-brokered peace talks between Kyiv and Moscow.
Speaking in the Ukrainian capital on Sunday, President Volodymyr Zelenskiy said the station risks a disaster worse than Chornobyl, if it was not transferred back to Ukrainian control.
