In Slavutych, the Ukrainian town built to house workers evacuated from the Chornobyl plant after the nuclear disaster, bells rang as hundreds of people filed through the streets.
In the capital, Kyiv, President Viktor Yushchenko placed a large bouquet of roses at a memorial marked by two stone slabs on a knoll.
He then traveled to the town of Chornobyl, some 18 kilometers from the nuclear plant, for another service to commemorate the victims of the world's worst nuclear accident.
Yushchenko paid tribute to "the Ukrainian heroes who died 20 years ago for the sake of our lives and the future" in the cleanup after the accident. "I am confident their deed will remain forever engraved in our lives," he said.
At a special parliamentary session, lawmakers demanded more help for the millions affected, and more information on what really happened. Parliamentary speaker Volodymyr Lytvyn reminded legislators that Ukraine will be dealing with the aftereffects of Chornobyl for many years to come.
"Unfortunately, today's commemoration of the anniversary of the disaster does not mean we can say good-bye to Chornobyl," he said. "It will remain with the Ukrainian people for more than one generation to come. But understanding the facts about the decay of radioactive materials and a number of unresolved technical problems should not demoralize us and we should not put off dealing with issues that must be dealt with today."
At 1:23 a.m. Kyiv time, a minute of silence was declared. That was the moment on April 26, 1986, when the nuclear reactor exploded, spewing out a radiation cloud that spread throughout Europe and as far as Japan.
The Chornobyl disaster contaminated large swathes of territory in Ukraine, Belarus, and Russia.
In Belarus, opposition groups were expected to hold a demonstration today in the capital, Minsk, against the government's handling of the catastrophe's aftermath.
(dpa, AFP, Reuters)
Mikhail Gorbachev prepares to address the 27th Congress of the Communist Party of the Soviet Union in Moscow on March 1, 1986, seven weeks before the Chornobyl accident (TASS)
SOVIET TELEVISION: Listen to the April 28, 1986, announcement on Soviet television of the Chornobyl nuclear accident two days earlier: Real Audio Windows Media
"There has been an accident at the Chornobyl nuclear power station. One of the atomic reactors has been damaged. Measures are being taken to eliminate the consequences of the accident. Assistance is being given to the injured and a government commission has been set up."
TELLING THE NATION: Listen to an excerpt from May 14, 1986, address to the nation by Soviet leader MIKHAIL GORBACHEV, in which he acknowledges the disaster for the first time and discusses measures being taken to limit the damage: Real Audio Windows Media
"All of you know that we have been struck by a misfortune recently -- the accident at the Chornobyl nuclear power plant. It has painfully affected the Soviet people and troubled the international community. We have, for the first time, confronted in reality the dreadful force of nuclear energy that got out of control. Considering the extraordinary and dangerous character of what happened in Chornobyl, the Politburo [of the Central Committee of the Communist Party] has taken in its hands all organization of efforts to eliminate the disaster and confine its consequences as soon as possible. The party, Soviet and economic authorities of Ukraine and Belarus have assumed an enormous share of work and responsibility. As of today 292 people have been hospitalized with radiation sickness of various levels of severity. Seven of them have died. On behalf of the Central Committee of the [Communist Party of the Soviet Union] and the Soviet government, I express deep sympathy to the families and relatives of those who have died, their colleagues, all those who have suffered from this misfortune, who have endured personal grief."
Read RFE/RL's coverage the 20th anniversary of the Chornobyl accident:
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