A Russian rocket has hit an apartment building in the western Ukrainian city of Lviv, killing at least four people, Ukraine's interior minister has said.
Ihor Klymenko added another 32 people were injured in what the mayor of Lviv said was "one of the biggest attacks" on the city's civilian infrastructure.
President Volodymyr Zelensky vowed a "tangible" response to the overnight assault by "Russian terrorists".
Russia's military has not commented on the reported attack.
Writing on Telegram, Mr Klymenko said at least seven people had been rescued from the apartment block, adding there were fears more people could be trapped under rubble.
Meanwhile, Lviv regional head Maksym Kozytskyi said a "critical infrastructure facility" was struck in the city. He gave no details.
Mr Kozytskyi said that Russia's "main goal is the destruction of the Ukrainian people... But we will win".
For months, Russia has been carrying out deadly missile and drone attacks on Ukrainian cities, often hitting civilian targets and causing widespread blackouts.
Only last week, 13 people were killed - including children - when a restaurant and shopping centre were struck in Kramatorsk, an eastern city close to Russian-occupied parts of Ukraine.
And despite being hundreds of kilometres from the main front lines in Ukraine's east and south, Lviv has also suffered Russian assaults.
On 20 June, Lviv officials reported that critical infrastructure had been hit in the city in a drone attack.
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