Ukrainian rescuers outside the city of Dnipro on Sunday recovered the body of a two-year-old girl from the rubble left by a Russian strike on a residential area.
On the other side of the border, Russian authorities asked villagers living in a heavily shelled district on the Ukraine border to leave their homes after deadly strikes prompted thousands to flee.
The Russian attack that hit the Pidhorodnenska suburb of the central city of Dnipro on Saturday came as Moscow has this week intensified aerial assaults on Ukraine.
"At night, a girl's body was retrieved from under the rubble of a house in the Pidhorodnenska community" outside Dnipro, Serhiy Lysak, governor of Dnipropetrovsk region, said on Sunday.
"She just turned two."
Officials said the strike killed the toddler, born in 2021, and wounded at least 22 others.
Five children were in hospital, including three boys who were in a critical condition, they added.
Kyiv also said a Russian strike had hit an airfield in central Ukraine overnight, which Moscow appeared to confirm on Sunday, saying it had struck military air bases with long-range weapons overnight.
The attacks came at the end of a week that saw Russia launch a series of air assaults on Kyiv, including rare day-time strikes.
The conflict, which has dragged on for more than 15 months, has escalated this week with increased attacks on both sides of the border.
Kyiv has for months said it is preparing for a major counteroffensive against Moscow's forces.
President Volodymyr Zelensky has said the country is "ready" but pleaded for more Western weapons to counter Russia's air superiority.
In a video published Sunday, the Ukrainian army appeared to call on soldiers to stay silent and said there will be no announcement on the start of the long-awaited offensive.
"Plans love silence," Deputy Defence Minister Ganna Malyar said on Telegram.
"The start will not be announced," she added, accompanying the video showing soldiers placing fingers on their mouths.
'Bombed and bombed'
Russian authorities asked residents of villages of a heavily shelled district in the Belgorod region that borders Ukraine to leave their homes.
Intensified Ukrainian shelling of the Shebekino district this week has left several people dead and forced thousands to leave the area for Belgorod city.
Belgorod governor Vyacheslav Gladkov said Sunday some 4,000 people left border villages and were placed in temporary housing.
He urged residents of several villages on the border to leave their homes.
"I ask that in the villages of, first of all, the Shebekino district that has been shelled, to listen to the position of authorities and leave -- temporarily leave -- their homes," Gladkov said on Telegram.
He said the goal was "to safeguard what is most important: your life and the lives of your close ones".
He said it was another "not calm night" in the district with "a lot of damage".
Tatiana Kozheleva, a 64-year-old pensioner who left Shebekino and was receiving humanitarian aid in Belgorod, told AFP there was almost "nothing left" of the small city.
"Our city Shebekino was bombed and bombed," she said.
"Our house was also hit by a shell," she said, adding that her balcony was damaged.
"We almost did not get out from under the shelling."
On Saturday, Ukrainian shelling killed two women in Russian border villages.
Gladkov said the authorities would take minors from border villages and the children of mobilised soldiers fighting in Ukraine to youth camps.
