At least three people were killed in the Moscow region when Ukraine attacked Russia with hundreds of drones overnight, local authorities said on Sunday.
Another five people were injured as several residential buildings were damaged and caught fire in the Moscow region, Governor Andrei Vorobyov wrote on Telegram.
Moscow Mayor Sergei Sobyanin said 12 construction workers were injured during an attack on an oil refinery in the Russian capital. The site itself remains operational, he added.
While Moscow is considered to have the most effective and extensive air defence system in Russia, the capital has been hit by Ukrainian drones in the past.
Last night's strikes were among the heaviest Ukrainian attacks seen in Moscow since the start of the Russian invasion more than four years ago, according to local media.
Passengers remained stuck for hours at Moscow's airports as take-offs and landings had to be temporarily suspended due to the attacks. Dozens of flights were cancelled or rerouted to other airports.
The Russian Defence Ministry said a total of 586 of Ukrainian drones had been downed across several regions overnight.
It is not possible to independently verify the claims.
Moscow Mayor Sobyanin said more than 120 drones had been intercepted within 24 hours over the capital alone.
A man was reportedly killed in the Belgorod region near the Ukrainian border when a lorry was hit by a drone. There was initially no official confirmation from authorities.
Ukraine also attacked the Russian-occupied Black Sea peninsula of Crimea overnight, damaging several apartment blocks in the capital Sevastopol, according to local authorities.
Debris from a downed drone struck a high-voltage power line, causing power cuts, Sevastopol Governor Mikhail Razvozhayev wrote on Telegram. However, the city’s power station was not hit, he said.
A total of 25 drones were shot down over the city and the Black Sea, according to Razvozhayev.
Russia annexed Crimea in 2014, though the peninsula is still recognized internationally as Ukrainian territory.
The Ukrainian attacks came after Russia launched one of its heaviest and longest air assaults on Ukraine earlier this week, with 24 killed in a strike on an apartment block in Kiev alone.
President Volodymyr Zelensky said on Sunday that a total of 52 people had been killed by Russian attacks this week. Another 346 people were injured, including 22 children, he wrote on X.
Russia deployed "more than 3,170 attack drones, over 1,300 guided aerial bombs, and 74 missiles of various types, most of them ballistic, against Ukraine" this week, Zelensky said.
"Our people need more protection, and everything that supports Ukraine’s air defense ultimately helps save lives," the president said, calling on allies to ramp up support.
Russia also attacked Ukraine again with some 300 drones overnight, Ukraine's air defence said on Sunday morning, adding that 279 drones had been intercepted.
