Intense artillery, rocket and drone attacks either side of the Russia-Ukraine frontline left at least 10 people dead and more than a dozen wounded, regional officials said.
Russian forces are pressing hard in the eastern Donetsk region ahead of May 9, when Moscow hails the Soviet Union's victory in World War II. Ukraine is desperately waiting for desperately needed US weapons promised as part of a new military aid package.
Russian attacks killed at least six in the Donetsk region, Ukrainian officials said. Four people were killed in Russian-occupied parts of southern and eastern Ukraine, according to Moscow-installed authorities.
In Ukrainian-held territory, a Russian strike on the village of Udachne, about 45 kilometres (28 miles) from the frontline killed three people, the region's governor Vadim Filashkin said.
"The Russians struck the village this afternoon. The administrative building, a cultural centre, a coffee shop and about 20 private houses were damaged," he said in a post on Telegram.
Another three people were killed in Kurakhivka, further south, the regional prosecutor's office said.
In Russian-held territory, a Ukrainian drone attack killed two people in the southern region of Zaporizhzhia, the Russian-installed government head said.
"A man and a woman were killed as a result of a strike on a civilian car. Their four young children were orphaned," Yevgeny Balitsky wrote on social media.
Ukrainian artillery fire killed two more in the Russian-occupied part of the southern Kherson region, officials there said.
The Kremlin claimed to have annexed the Kherson and Zaporizhzhia regions in late 2022, though Russian forces are still battling to gain full control over them.
The two frontline regions saw intense fighting in 2022 and the summer of 2023, when Ukraine launched a failed counteroffensive in the south.
The brunt of the fighting has since moved to the Donetsk region, which is also claimed by Moscow as Russian territory.
Later on Thursday, a Russian attack on a railway station in the northeastern Kharkiv region injured at least 10 people, Ukrainian governor Oleg Synegubov said.
In the Russian border region of Bryansk, a Ukrainian drone hit a bus, injuring four people, the Russian governor said.
And in the Russian-controlled part of Ukraine's Zaporizhzhia region, a strike by Kyiv's forces on a multi-storey residential building injured at least three, Balitsky said on Telegram.
