Russia and Ukraine have conducted overnight drone strikes against each other, killing at least five people.
Officials in Kyiv said a massive overnight Russian drone strike on the city had killed at least two people and injured six more.
The attack in the early hours of Tuesday also hit at least two residential buildings, triggering fires and disrupting electricity and water supplies.
Meanwhile, Russian officials said at least three people had been killed in a Ukrainian strike in the Rostov region.
The latest attacks come after Ukrainian President Volodymyr Zelensky welcomed proposed changes to the controversial 28-point US peace plan for ending the war with Russia.
Kyiv's military administration chief, Tymur Tkachenko, said a fire had broken out at a high-rise residential apartment building in the Dniprovskyi district, forcing the evacuation of its residents.
Emergency services on the scene reported that 18 people had been rescued, including three children, and the search for victims was ongoing.
A second high-rise apartment in the Pechersk district was also set ablaze after being hit during the strikes, according to Kyiv's mayor, Vitali Klitschko.
Ukraine's air defence units responded to the attack as explosions were heard across Kyiv, with residents urged to seek shelter.
Ukraine's Ministry of Energy confirmed a massive, combined enemy attack on the country's energy infrastructure.
In Rostov, Russian officials reported the death toll from a Ukrainian strike had risen to three, with several others injured.
These escalations in violence coincide with ongoing peace negotiations, amid mixed reactions to proposed revisions to a potential peace plan.
