A Russian strike on the south Ukrainian town of Vilniansk killed at least seven people, Kyiv said, in an attack that came hours after Russia said a Ukrainian drone killed five people on its border village.
Both countries said two children were killed in each attack, in a deadly day in the more than two-year war.
Kyiv also said four people were killed in eastern frontline villages in the Donetsk region.
Ukrainian President Volodymyr Zelensky warned the death toll in Vilniansk -- near the regional hub of Zaporizhzhia -- may increase.
"Seven people, including two children, have been killed by a Russian missile strike in the Zaporizhzhia region," Zelensky said on social media.
He called for his Western allies to speed-up weapons deliveries, saying: "Any delay in decisions in this war means the loss of human lives."
Ukraine's Internal Minister, Igor Klimenko, said 18 people -- including four children -- were wounded in Vilniansk.
He posted images of a local burnt out low-rise building and blackened cars.
The head of the Zaporizhzhia region, Ivan Fedorov, earlier said a "critical infrastructure facility, a shop and residential buildings were damaged" in the strike.
Vilniansk lies 29 kilometres (18 miles) north-east of the city of Zaporizhzhia, the main regional city which is under Ukrainian control.
Russia's attack on Vilniansk came hours after Moscow said a Ukrainian drone on a house in a Russian border village killed five people, including two children.
Five dead in Russian village
Moscow said the drone hit a house in the village of Gorodishche, a tiny village in Russia's Kursk region, just a few metres from the border with Ukraine.
"To our great grief, five people were killed ... including two small children. Another two members of the family are in a serious condition," Kursk governor Alexei Smirnov said in a post on Telegram.
The attack was with a "copter"-style drone, he added, a small device that can be fitted to carry grenades or other explosives that are dropped over targets.
Both sides have used drones, including larger self-detonating craft with ranges of up to hundreds of kilometres, extensively throughout the conflict which began in February 2022.
Ukraine has stepped up its attacks on Russian territory this year, targeting both energy sites that it says fuel Russia's military, as well as towns and villages just across the border.
Fighting in Ukraine has intensified in several directions as Russia has launched offensives from several directions, taking advantage of Kyiv being on the back foot militarily.
Four dead in eastern Ukraine
Kyiv's army said Saturday Moscow was attacking from several directions and that "the total number of hostile attacks along the entire frontline has now risen to 90."
Ukrainian officials reported deadly attacks on Saturday morning that killed four people in eastern villages.
"In (the village of) Zarichne, Russians killed three people," Vadym Filashkin, the head of the Donetsk region, said on social media.
The office of Ukraine's General Prosecutor later said another person, a resident of the eastern village of New York "also sustained fatal injuries."
New York has been intensely attacked since mid-June as Russian forces push towards the city of Toretsk, further north.
In the central city of Dnipro, police said they found a woman who was killed in an attack a day earlier that also wounded 13 people.
"Police identified a woman killed in a missile attack on Dnipro city. She is a 76-year-old resident of a destroyed apartment block," Ukraine's National Police said in a statement.
It said the number of wounded in the attack rose to 13, "including an infant and a pregnant woman."
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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