You're reading: Ukraine prepares to mark 25 years since Chernobyl

Former Soviet republics prepared to mark 25 years since the Chernobyl power station exploded in the world's worst nuclear accident, endangering hundreds of thousands of lives and contaminating pristine forests and farmland.

The blast on April 26, 1986, spewed a cloud of radioactive fallout over much of Europe and forced hundreds of thousands from their homes in the most heavily hit areas in Ukraine, Belarus and western Russia.

Scientists are deeply divided on how many have died as a result of the explosion, which released about 400 times more radiation than the U.S. atomic bomb dropped over Hiroshima.

An international donors conference in Kiev last week raised 550 million euros ($798 million) of the 740 million euros needed to build a new shelter and a storage facility for spent fuel.

Soviet officials did not report the disaster for several days.

Even in the plant workers’ town of Pripyat, few knew what had happened when the plant’s No. 4 reactor blew up around 1:30 in the morning. The official acknowledgment came three days later.

Ukrainian President Viktor Yanukovich and Russian Orthodox Patriarch Kirill will commemorate the victims of the nuclear accident with prayers and candle-lighting in Kiev tonight before they travel to the Chernobyl station on Tuesday.

A 19-mile (30-kilometer) area around the plant has been uninhabited except for occasional plant workers, and several hundred local people who returned to their homes despite official warnings.

Vasily Voznyak, the head of the Soviet government’s Chernobyl department in 1986-1990, told a news conference on Monday that officials were totally unprepared for the accident:

"Neither the civil defense, nor the station’s management, nor the Soviet party organs in the region were ready for an accident of such a global scale," he said in Moscow.

Japan is struggling to bring the radiation-spewing Fukushima Dai-ichi nuclear plant under control after last month’s earthquake and tsunami triggered another nuclear disaster.

Evgeny Akimov, a nuclear engineer and the former head of the Chernobyl containment facility, said he is convinced that the scale of the disaster at the Fukushima plant is far smaller since "no fuel has been discharged outside the reactor vessels".

The U.N.’s World Health Organization said at a Kiev conference last week that among the 600,000 people most heavily exposed to radiation, 4,000 more cancer deaths than average are expected to be eventually found.

Soviet authorities initially offered a generous package of benefits to Chernobyl cleanup workers. But over time the benefits have been cut back.

About 2,000 veterans of the Chernobyl clean up rallied in Kiev earlier this month to protest cuts in their benefits and pensions after Ukraine’s Yanukovich said fulfilling the past promises to Chernobyl workers was "beyond the government’s strength" amid the financial downturn.

Chernobyl veterans in Belarus are facing similar cuts.