Kyiv mayor Vitali Klitschko said a suspected missile strike on a 24-storey apartment building triggered a collapse, with people likely trapped under the rubble.
“At least 14 people were injured across the city, according to early reports,” he added.
“A fire had broken out in the Podil district on the grounds of a non-residential property and a nine-storey apartment building was on fire after debris apparently struck the roof,” the mayor said.
“In the Obolon district, cars are burning after being struck by falling missile debris.
“There are also fires at two locations in open areas, including one near a kindergarten,” Klitschko said on Telegram.
Thousands of residents of Kyiv were taking refuge inside metro stations and other shelters after air raid warnings.
Most of the country was under air raid warnings early on Tuesday.
“Another attack on Dnipro, in Ukraine’s east, killed four people and injured 16 others,” regional governor Oleksandr Hanzha said on Telegram.
All those injured were hospitalised and were reported to be in moderate condition.
A two-story building was partially destroyed, while several apartments in a four-storey building were damaged.
Ukrainian President Volodymyr Zelensky on Monday reiterated warnings of a possible massive Russian strike and urged residents to pay special attention to air raid alerts.
“Intelligence warnings regarding Russian strikes remain in effect. A massive strike is possible, they have prepared one,” Zelensky said in his nightly video address.
“Our defenders are ready 24/7 to the fullest extent possible with the supplies currently available,” he said.
Russia last week warned that it intended to launch “systematic strikes” on targets in Kyiv linked to the Ukrainian military as well as decision-making centres, and urged foreigners to leave.
It said the action was in response to a drone strike last month on a dormitory in Ukraine’s Russian-held Luhansk region, which killed 21 people. Ukraine denied carrying out the attack.
In Ukraine’s northeastern Kharkiv region, governor Oleh Syniehubov said on Telegram that at least six people were wounded, including an 11-year-old girl, in Russian shelling overnight.
Reuters could not independently verify the reports.
Russia has targeted Ukraine’s power supplies and infrastructure while Ukraine has stepped up attacks on oil facilities inside Russia this year, sometimes resulting in casualties. Both sides deny targeting civilians.
The war in Ukraine has ground on for more than four years since Russia launched its full-scale invasion in February 2022.
Efforts to end the conflict have made little progress with the US administration of Donald Trump focused on conflicts in the Middle East.