The governor of Ukraine's central Dnipropetrovsk region says 13 civilians were killed by Russian shelling overnight in Nikopol and Marhanets, and 11 more people injured, five of them seriously.
Valentyn Reznichenko said two of the victims died at Marhanets Hospital despite efforts to save them.
Reznichenko described the scene of the attacks, on the Kakhovka Reservoir of the Dnieper River in south-central Ukraine, in a burst of Telegram posts early on August 10.
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"We had a terrible night.... We have 11 dead.... All peaceful people who had plans for life today," Reznichenko wrote. He later revised the death toll to 13.
"It is very difficult to get bodies from under the rubble," he added.
Ukrainian President Volodymyr Zelenskiy said later that Ukraine would respond to the Russian shelling of Marhanets.
Zelenskiy said in his nightly video address on August 10 that Kyiv "will not leave today's Russian shelling of the Dnipropetrovsk region unanswered."
Ukrainians and the country's allies must think about "how to inflict the greatest possible losses on the occupiers in order to shorten the war," he said.
The areas that were reportedly struck are about 20 kilometers away and on the opposite side of the Dnieper from the Zaporizhzhya nuclear power plant, which was seized early in the 5-month-old invasion and has been shelled several times in the past week, sparking intense international concern.
Marhanets was worst hit, the governor said, with 20 multiple-story buildings damaged, including schools, a dormitory, and a cultural center.
Andriy Yermak, Zelenskiy's chief of staff, said Russia was launching attacks with impunity from Zaporizhzhya knowing it was risky for Ukraine to fight back.
"The Russian troops can't win battles, so they keep attacking the cities, hiding at the Zaporizhzhya NPP facilities and blackmailing the world with nuclear incidents," Yermak said on Twitter.
Russia has not commented on the allegations of the attack on Marhanets, and the Ukrainian side's claims could not be independently verified. Moscow has said it does not deliberately target civilians.
Russia's envoy to talks in Vienna to revive the Iran nuclear deal, Mikhail Ulyanov, told the Rossiya-24 TV channel on August 10 that Ukraine’s claims that Russia allegedly rigged the power plant with mines were false.
UN Secretary-General Antonio Guterres called on August 8 for international inspectors to be given access to the Zaporizhzhya plant after Ukraine and Russia traded accusations over the recent shelling of the facility.
"Any attack on a nuclear plant is a suicidal thing," Guterres said.
The Group of Seven (G7) condemned Russia's occupation and called on Moscow to immediately hand back full control of the plant.
Ukrainian staff operating the plant "must be able to carry out their duties without threats or pressure. It is Russia's continued control of the plant that endangers the region," the G7 foreign ministers said in a statement.
The ministers stressed the importance of allowing experts from the International Atomic Energy Agency to be sent to the power plant to address nuclear safety and security concerns.
They warned that Russia's actions significantly increase the risk of a nuclear incident and put the people of Ukraine, neighboring states, and the world at risk.