Ceremonies have begun to mark the 25th anniversary of the Chornobyl nuclear disaster in Ukraine.
A bell in Kyiv tolled 25 times to mark the number of years since the disaster.
Russian Orthodox Patriarch Kirill told hundreds attending a service for the victims that the world had not seen a worse catastrophe in peaceful times.
Later today, Ukraine’s President Viktor Yanukovych and Russia’s President Dmitry Medvedev are to attend memorial ceremonies in Chornobyl.
President Alyaksandr Lukashenka of Belarus, which lies just north of Chornobyl, is not joining the commemorations in Ukraine, his press service said.
On April 26, 1986, an explosion at the Chornobyl nuclear power plant sent a cloud of radiation over much of Europe and forced hundreds of thousands from their homes.
Ukraine, Belarus, and Western Europe were most impacted by the disaster.
The explosion released about 400 times more radiation than the U.S. atomic bomb dropped over Hiroshima.
Hundreds of thousands were sickened and forests and farmland still remain contaminated.
The UN’s World Health Organization says that among the 600,000 people most heavily exposed to the radiation, 4,000 more cancer deaths than average are expected to be eventually found.
The Chornobyl anniversary has gained an eerily contemporary resonance after the March 11 earthquake and tsunami in Japan which damaged reactors at the Fukushima Daiichi power plant and prompted leaks of radiation.
compiled from agency reports