KYIV/MOSCOW/VIENNA/MINSK - At least 27 people were killed in a Russian attack on the Ukrainian capital on Thursday, Tymur Tkachenko, head of the Kyiv City Military Administration, said.

As of 9 pm local time (1800 GMT), search and rescue efforts were still underway, with at least eight people reported missing, Tkachenko wrote on Telegram.

Kyiv Mayor Vitali Klitschko described the assault as the "most massive" Russian attack on the capital, saying it involved cruise and ballistic missiles, as well as drones. He previously said that at least 86 people were injured in the attack.

Damage was reported across all districts of the city, Klitschko wrote on Telegram, adding that the heaviest destruction occurred in the Darnytskyi district, where part of an apartment building collapsed.

The Ukrainian Air Force said that Russia launched 496 drones and 74 missiles across Ukraine in the overnight attack, with Kyiv as the primary target. Air defense forces intercepted 476 drones and 48 missiles. 

Meanwhile, the Russian Armed Forces have struck Ukrainian transport infrastructure, long-range drone launch sites, and other military targets in 153 locations, the Russian Defense Ministry said Thursday.

The strikes were carried out using operational-tactical aviation, strike drones, missile forces, and artillery, the ministry said.

Fire station backing Zaporizhzhia nuclear plant

International Atomic Energy Agency (IAEA) Director General Rafael Grossi on Thursday condemned Tuesday's drone attacks as "unacceptable" after they caused significant damage to a fire station supporting emergency response at the Zaporizhzhia Nuclear Power Plant.

According to an IAEA statement, the agency's team at the plant confirmed significant damage to a fire station in the nearby city of Enerhodar. Grossi said the station plays an important role in supporting the plant's emergency response capability.

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During a visit to the site on Wednesday, the IAEA team observed damage to the building and several firefighting vehicles, which had largely undermined the station's operational capacity.

The facility provides important backup support to the plant's own fire brigade in the event of a large-scale emergency at the plant, the statement said.

Drone attack injures 3 on Belarusian bus 

Three people were injured in an attack on a Belarusian passenger bus near the Krasny Kamen checkpoint in Russia's Bryansk region, the Belarusian Health Ministry said on Thursday.

The incident occurred at approximately 11:55 am when a drone targeted a bus traveling from Minsk to Anapa, which was parked in a vehicle lot near the border crossing. The bus, which had 19 passengers and two drivers onboard, sustained damage during the attack.

The injured individuals have received necessary medical treatment, the ministry added.