Russia launched a rush-hour barrage of missiles towards Ukraine on Thursday, killing at least one person, the day after Kyiv secured Western pledges of dozens of modern battlefield tanks to try to push back the Russian invasion.
Moscow reacted with fury to the German and American announcements, and has in the past responded to apparent Ukrainian successes with air strikes that have left millions without light, heat or water.
The Ukrainian military said it had shot down all 24 drones sent overnight by Russia, including 15 around the capital, with no damage reported.
But soon afterwards, air raid alarms sounded across Ukraine as people were heading to work, and senior officials said air defences were shooting down incoming missiles.
The Kremlin said on Thursday it saw the promised delivery of Western tanks to Ukraine as "direct involvement" of the US and Europe in the 11-month-old conflict, something both deny.
In the capital, crowds of people took cover in underground metro stations. Mayor Vitali Klitschko said one person had been killed and two wounded when a missile hit non-residential buildings in the south of the city.
Kyiv's military administration said more than 15 missiles fired at Kyiv had been shot down, but urged people to remain on shelters.
DTEK, Ukraine's largest private energy producer, said it was conducting emergency power shutdowns in Kyiv, the surrounding region and also the regions of Odesa and Dnipropetrovsk because of the imminent danger.
In Odesa, the Black Sea port designated a "World Heritage in Danger" site on Wednesday by the UN cultural agency Unesco, Russian missile strikes damaged energy infrastructure, the district military administration said.
Western analysts say the attacks on Ukraine's cities are more an attempt to break morale than a strategic campaign.
Both sides are expected to mount new ground offensives come the spring, and Ukraine has been seeking hundreds of modern tanks in the hope of using them to break Russian defensive lines and recapture occupied territory in the south and east.
Both Ukraine and Russia have so far relied primarily on Soviet-era T-72 tanks.
'Fist of freedom'
"The key now is speed and volumes. Speed in training our forces, speed in supplying tanks to Ukraine. The numbers in tank support," President Volodymyr Zelensky said in his nightly video address on Wednesday.
"We have to form such a 'tank fist', such a 'fist of freedom'."
Maintaining Kyiv's drumbeat of requests, Zelensky said he had spoken to Nato secretary-general Jens Stoltenberg and asked for long-range missiles and aircraft.
Ukraine's allies have already provided billions of dollars worth of military support, including sophisticated US missile systems that have helped turn the tide of the war in the last six months.
The US has been wary of deploying the difficult-to-maintain Abrams but had to change tack to persuade Germany to send to Ukraine its more easily operated German-built Leopards.
Germany will send an initial company of 14 tanks from its stocks, which it said could be operational in three or four months, and approve shipments by allied European states with the aim of equipping two battalions – in the region of 100 tanks.
The Leopard is a system that any Nato member can service, and crews and mechanics can be trained together on a single model, Ukrainian military expert Viktor Kevlyuk told Espreso TV.
"If we have been brought into this club by providing us with these vehicles, I would say our prospects look good."
US President Joe Biden said the 31 M1 Abrams tanks that Washington will provide posed "no offensive threat" to Russia.
But Sergei Nechayev, Russia's ambassador to Germany, on Wednesday called Berlin's decision "extremely dangerous", saying that it "takes the conflict to a new level of confrontation".
Fighting in east Ukraine
Since invading Ukraine on Feb 24 last year, Russia has shifted its publicly stated goals from "denazifying" and "demilitarising" its neighbour to confronting a purportedly aggressive and expansionist US-led Nato alliance.
The Russian invasion has killed thousands of civilians, forced millions from their homes and reduced entire cities to rubble.
The heaviest fighting for now is around Bakhmut, a town in eastern Ukraine with a pre-war population of 70,000 that has seen some of the most brutal combat of the war.
Ukraine's military said Russia was attacking "with the aim of capturing the entire Donetsk region and regardless of its own casualties".
The Russian-installed governor of Donetsk said on Wednesday that units of Russia's Wagner contract militia were moving forward inside Bakhmut, with fighting on the outskirts and in neighbourhoods recently held by Ukraine.
Reuters could not verify the battlefield reports.