An explosion near the central Ukrainian city of Dnipro on Saturday hit a two-storey dwelling, injuring 20 people including five children, and rescuers pulled residents out from under the rubble, the regional governor said.
Serhiy Lysak, writing on the Telegram messaging app, said three of the children were in serious condition. A total of 17 people were being treated in hospital.
Media reports said emergency teams had pulled four people from under rubble in the town known as the Pidhorodnenska community. Lysak said another child was likely still trapped.
Reports on social media said a Russian missile caused the explosion and that an emergency services building was also hit.
There was no confirmation of a missile strike from Ukrainian military officials.
President Volodymyr Zelenskiy, also writing on Telegram, said the explosion occurred between two dwellings.
"Unfortunately, there are people under the rubble," Zelenskiy wrote. "Once again, Russia proves it is a terrorist state."
Moscow denies its military forces target civilians.
Pictures posted on social media showed rescue teams working at a shattered, smouldering building amid piles of twisted building materials.