Rescuers initially said nine people were killed, but interior minister Igor Klymenko later told reporters eight were dead, while more than 70 were injured.
Rescuers were working to recover people from the rubble of buildings, he added.
Olena Davydiuk, a 33-year-old lawyer in Kyiv, told AFP she saw windows breaking and doors “falling out of their hinges” during the barrage.
“People were being pulled out of the rubble. They said that there were dead people there too,” she added.
“PHONE CALLS UNDER RUBBLE”
Russia fired at least 70 missiles and 145 drones at Ukraine between late Wednesday and early Thursday, the main target being Kyiv, the Ukrainian air force said.
Of the 215 projectiles, 112 were “confirmed to have been shot down”, it wrote on Telegram.
Loud blasts sounded over the Ukrainian capital at around 1am, after air raid sirens rang out across Kyiv warning residents to head to shelters, AFP journalists on the ground said.
Through the night, rescue workers were scouring through the rubble of destroyed buildings and tackling blazes in apartment blocks. The interior ministry said damage was recorded at 13 separate locations across the capital.
“Phone calls can be heard from under the rubble – the search will continue until we are confident that we have found everyone,” Klymenko said, adding that two children were unaccounted for.