The attack in Dnipro, Ukraine's fourth-largest city, was part of a large Russian missile and drone barrage across the country that targeted power infrastructure and also killed a worker at an energy company in Kharkiv, farther north, a local official said.
It comes as fighting for the strategic city of Pokrovsk in the country's east has reached a key stage, with both Ukraine and Russia vying to persuade US President Donald Trump that they can win on the battlefield.
A fire broke out and several apartments were destroyed in the nine-storey building in Dnipro, the emergency services said.
Rescuers recovered the bodies of three people, while two children were among the injured.
Russia fired a total of 458 drones and 45 missiles, including 32 ballistic missiles.
Ukrainian forces shot down and neutralised 406 drones and nine missiles, the air force said, adding that 25 locations were struck.
Authorities switched off power in several regions due to the attacks, Ukrainian Energy Minister Svitlana Grynchuk said in a post on Facebook.
Russia has been pummelling Ukraine with near-daily drone and missile strikes, killing and injuring civilians.
The Kremlin says its only targets are linked to Ukraine's war effort.
Russia's Defence Ministry asserted on Saturday that the night-time strikes hit military and energy sites supplying Ukrainian forces.
Russia and Ukraine have traded almost daily assaults on each other's energy targets as US-led diplomatic efforts to stop the nearly four-year war had no effect on the battlefield.
Ukrainian Prime Minister Yulia Svyrydenko said in a post on X that the strikes damaged "several major energy facilities" around Kharkiv and Kyiv as well as in the central Poltava region.
An energy company worker was killed in Kharkiv, Ukraine's second city, regional head Oleh Syniehubov said in a post on Telegram.
"We are working to eliminate the consequences of the attacks across the country. The focus is on the rapid restoration of heating, electricity and water supply," Svyrydenko added.
Russian forces, meanwhile, repelled a "massive" night-time strike on energy facilities in the southern Volgograd region, its governor Andrei Bocharov said on Saturday, two days after Ukraine said it had hit a key oil refinery there with long-range drones.
Bocharov added that the strike knocked out power in parts of the region's northwest but caused no casualties.
Russia's Defence Ministry said on Saturday that its forces shot down 82 Ukrainian drones during the night, including eight over the Volgograd region.
Two people were injured in the neighbouring Saratov region after a Ukrainian drone strike blew out windows in an apartment block, according to regional governor Roman Busarin.
A van carrying an Austrian and a Spanish journalist was attacked by a drone near the front line in eastern Ukraine on Saturday.
The passengers included Austrian Broadcasting Corporation (ORF) correspondent Christian Wehrschütz.
"A drone caught us but luckily everyone is fine," Wehrschütz wrote on Instagram, where he posted a video of the incident filmed with his mobile phone.
According to the ORF, the incident took place in the Donetsk region.
The correspondents were travelling with the Proliska aid organisation to the city of Kostiantynivka.
The video shows the occupants fleeing the vehicle before an explosion can be heard.
Afterwards, a torn-off bumper, burning debris and smoke can be seen.
with DPA
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