Russian shelling hit Ukraine's southern port city of Mykolaiv overnight, according to the city's mayor.
Mykolaiv and the surrounding region have been targeted daily for weeks in the conflict.
The city's mayor Oleksandr Senkevych did not say whether there were any injuries in the overnight attack, which he said damaged some homes.
A child was killed and five people were injured after rocket attacks on Saturday, governor Vitaliy Kim said.
Mykolaiv, which sits on the Southern Bug River around 20 miles upstream from the Black Sea, is a major port and shipbuilding centre.
In Kharkiv, Ukraine's second-largest city, Russian shelling late Saturday set a large wooden restaurant complex on fire, according to the region's emergency service.
One person was killed and two injured in shelling in the region, governor Oleh Syniehubov said.
Pavlo Kyrylenko, governor of the eastern Donetsk region where Russian forces have been trying to take full control, said four people were killed in shelling on Saturday.
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The head of the UN nuclear watchdog said on Saturday that the Russian-controlled Zaporizhzhia nuclear plant in Ukraine was disconnected from its last external power line but was still able to run electricity through a reserve line amid sustained shelling in the area.
International Atomic Energy Agency (IAEA) Director-General Rafael Grossi said in a statement that the agency's experts, who arrived at Zaporizhzhia on Thursday, were told by senior Ukrainian staff that the fourth and last operational line was down.
The three others were lost earlier during the conflict.
But the IAEA experts learned that the reserve line linking the facility to a nearby thermal power plant was delivering the electricity the plant generates to the external grid, the statement said.
The same reserve line can also provide backup power to the plant if needed, it added.