Russian rocket strike on Lviv kills four, says city mayor PHOTO

A Russian rocket has hit an apartment building in the western Ukrainian city of Lviv, killing at least four people.

The announcement came from Ukraine's Interior Minister Ihor Klymenko, according to BBC.

He added that another 32 people were injured in what the Lviv city Mayor Andriy Sadovyi said was "one of the biggest attacks" on the city's civilian infrastructure.

President Volodymyr Zelenskyy vowed a "tangible" response to the overnight assault by "Russian terrorists".

Russia's military has not commented on the reported attack.

Writing on Telegram, Klymenko said at least seven people had been rescued from the apartment block, adding there were fears more people could be trapped under rubble.

Sadovyi posted a video showing broken windows in the struck building, which appeared to have four floors.

Damaged cars and debris were also seen in the footage.

"Many apartments are damaged - more than 50," the mayor said in a short video message.

Mayor Sadovyi said people had been pulled from the rubble a short while ago, but rescue teams were continuing their search, fearing that more residents could be trapped there.

The mayor later recorded a new video address after the scale of the devastation became clearer.

He said several roofs of buildings had blown away, while a school and the polytechnic university dormitories were also damaged.

Meanwhile, Lviv regional head Maksym Kozytskyi said a "critical infrastructure facility" was struck in the city, providing no details.

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.

Despite being hundreds of kilometres from the main front lines in Ukraine's east and south, Lviv has also suffered Russian assaults.

On June 20, Lviv officials reported that critical infrastructure had been hit in the city in a drone attack.