By Tom Balmforth and Max Hunder
KYIV -Ukraine's president urged the world to act much faster to force Russian troops to vacate Europe's largest nuclear power plant after the site was cut from electricity for hours in an incident he said risked an international radiation disaster.
President Volodymyr Zelenskiy said Russian shelling on Thursday had sparked fires in the ash pits of a nearby coal power station that disconnected the Zaporozhzhia plant from the power grid. A Russian official said Ukraine was to blame.
Back-up diesel generators ensured power supply vital for cooling and safety systems at the plant, Zelenskiy said, praising the Ukrainian technicians who operate the plant under the gaze of the Russian military.
"The key thing is...international pressure is needed that will force the occupiers to immediately withdraw from the territory of the Zaporizhzhia nuclear power plant," he said in a video address on Thursday evening.
"The IAEA and other international organizations must act much faster than they're acting now. Because every minute the Russian troops stay at the nuclear power plant is a risk of a global radiation disaster," he said, referring to the United Nations nuclear watchdog.
Residents in Zaporozhzhia city, 50 km northeast of the plant and some 435 km (270 miles) to the southeast of Kyiv, expressed alarm at the situation.
"Of course I am scared. Everyone is scared, we don’t know what will happen next, what is waiting for us every next minute, second," said social media manager, Maria Varakina, 25.
School teacher Hanna Kuz, 46, said people were afraid that the Ukrainian authorities might not be able to warn residents in time in case of radiation fallout.
Ukraine's state nuclear company Energoatom said one of the plant's two functioning reactors had been reconnected to the grid and was again supplying electricity after it fully disconnected on Thursday.
Vladimir Rogov, a Russian-appointed official in the occupied town of Enerhodar near the plant, blamed Ukrainian armed forces for Thursday's incident, saying they caused a fire in a forest near the plant.
"This was caused by the disconnection of power lines from the Zaporizhzhia nuclear power station as a result of provocations by Zelenskiy's fighters," Rogov wrote on Telegram. "The disconnection itself was triggered by a fire and short circuit on the power lines."
Russia's Defence Ministry said on Friday its forces had destroyed a U.S.-made M777 howitzer which it said Ukraine had used to shell the Zaporizhzhia plant. Satellite images showed a fire near the plant but Reuters could not verify its cause.
Energoatom said Thursday's incident had been the first complete disconnection of the plant, which has become a hotspot in the six-month-old war.
Regional authorities in Zaporizhzhia said more than 18,000 people across several settlements remained without electricity on Friday due to damage caused to power lines.
A Reuters cameraman said there was electricity as normal on Friday in the city of Zaporizhzhia.
Russia invaded Ukraine in February, captured the plant in March and has controlled it since, though Ukrainian staff still run it. Russia and Ukraine have accused each other of shelling the site, fuelling fears of a nuclear disaster. Zaporizhzhia city remains controlled by Ukrainian authorities.
The United Nations is seeking access to the plant and has called for the area to be demilitarised.
Germany on Friday condemned Russia's continued occupation of the plant, calling the situation "very, very dangerous".
Paul Bracken, a national security expert and professor at the Yale School of Management, said the concern was that artillery shells or missiles could puncture the reactor walls and spread radiation far and wide, much like the 1986 accident involving the Chornobyl reactor.
A failure at the Zaporizhzhia plant could "kill hundreds or thousands of people, and damage environmentally a far larger area reaching into Europe," Bracken said.
"Russian Roulette is a good metaphor because the Russians are spinning the chamber of the revolver, threatening to blow out the brains of the reactor all over Europe," he said.
Russia's ground campaign has stalled in recent months after its troops were repelled from the capital Kyiv but fighting continues along the frontlines to the south and east.
Russian forces control territory along Ukraine's Black Sea and Sea of Azov coasts, while the conflict has settled into a war of attrition in the eastern Donbas region.
Explosions were heard early on Friday in the southern city of Mykolaiv, a battleground as Russian forces try to push westwards along the coast to cut Ukraine off from the Black Sea. The immediate cause of the blasts was unclear, regional governor Vitaliy Kim said.
Ukraine said it had repulsed Russian assaults on Bakhmut and Soledar in the eastern Donetsk region and struck ammunition depots and enemy personnel in the southern Kherson region.
Ukrainian forces fired some 10 rockets from a U.S.-supplied HIMARS multiple rocket launcher at the town of Stakhanov in the eastern Donbas region, pro-Moscow breakaway officials in Luhansk were quoted by Russia's TASS news agency as saying.
Russian state news agency TASS said the deputy traffic police chief in the occupied Ukrainian city of Berdiansk was killed on Friday in a bombing. Its Russian-installed administration blamed the blast on "Ukrainian saboteurs".
Ukraine's Defence Ministry did not respond to a request for comment. The Odesa regional administration said the officer was wounded in an explosion carried out by what it called unidentified partisan fighters in Berdiansk.
Reuters was unable to verify the battlefield reports of either side.
The Kremlin says its aim is to "denazify" and demilitarise Ukraine and remove perceived security threats to Russia. Ukraine and the West say this is a baseless pretext for a war of conquest.
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