A Russian strike killed three people in a residential district of the eastern Ukrainian city of Kostiantynivka on Saturday, the regional governor said.

Fourteen other people were wounded in the attack, which also damaged four apartment buildings and a hotel, Donetsk governor Pavlo Kyrylenko said.

"Rescuers and law enforcement officials are working at the scene of the tragedy to help people and carefully document yet another crime by the Russian occupiers on our land," he wrote on Telegram.

Twisted metal and the charred remains of household items and at least one car lay scattered across the courtyard as rescuers worked to clear the rubble. Fresh bloodstains were also visible.

Factory worker Iryna Maltseva, 42, said she was watching television when the explosion violently rattled her living room.

"I opened my eyes and everything was blown out," she said. "I was covered in blood. Mom was sitting in the bedroom, also covered in blood."

Earlier Saturday, Kyrylenko said at least four people had been killed and seven wounded throughout the region from Russian strikes over the past 24 hours.

President Volodymyr Zelenskyy said Friday the situation at the front remained "extremely acute,", particularly in the Donetsk region where Russia is stepping up an offensive.

Moscow invaded Ukraine last February but in recent weeks fighting has slowed to an attritional battle with neither side making significant gains.

Kyiv has repeatedly warned that Russian forces would attempt to mount another offensive sometime in the coming weeks or months.