A total of 11 people were killed during Russian drone and missile strikes on Ukraine throughout the course of Thursday, a spokesperson for the State Emergency Service said.
Another 11 people were wounded in the attacks, which spanned 11 regions and also damaged 35 buildings, Oleksandr Khorunzhyi told Ukrainian television.
Kyiv's mayor urged residents to stay in shelters on Thursday morning after an explosion was heard in Ukraine's capital amid what officials said was a Russian missile salvo.
The missile strikes followed a drone attack overnight, one day after Ukraine secured pledges of supplies of main battle tanks from Germany and the United States to beef up its troops -a move that infuriated Russian officials.
Air force spokesperson Yuriy Ihnat said as many six Tu-95 warplanes had taken off from the Arctic region of Murmansk in northern Russia and launched long-range missiles.
He said he expected a volley of more than 30 missiles and that air defense forces were trying to shoot them down.
Ukrainian air defenses downed more than 15 Russian missiles fired toward the capital Kyiv during Moscow's latest round of air strikes, city officials said on Thursday.
"The enemy launched more than 15 cruise missiles in the direction of Kyiv. Thanks to the outstanding work of our air defenses all the targets were destroyed," the Kyiv City Military Administration quoted its head, Serhiy Popko, as saying on Telegram.
"Despite this, the danger of air strikes has not passed," he added. "Remain in shelters until the end of the air-raid alert."
Ukraine declared an air raid alert over the whole country on Thursday, and senior officials said air defenses units were shooting down incoming Russian missiles.
Two missiles were spotted over the territory of the Mykolaiv region, its governor, Vitaly Kim, said on the Telegram messaging app.
"Missiles are flying inside the territory of Ukraine. At least two northwest through Mykolaiv region," he said.
Officials told the public to take shelter.
"The first Russian missiles have been shot down," Andriy Yermak, head of the president's office said.
Russia has targeted critical infrastructure with missile and drone strikes since October, causing sweeping blackouts and other outages during winter.
DTEK, Ukraine's largest private energy producer, said it was conducting emergency power shutdowns in the capital, Kyiv, the surrounding region, and also the regions of Odesa and Dnipropetrovsk due to a danger of missile attack.
Overnight, the military said its anti-aircraft defenses had shot down all 24 drones sent by Russia.
Fifteen of the drones were downed around the capital Kyiv where there were no reports of any damage.