Ukraine has said it downed 74 out of 75 Russian attack drones overnight, in what Kyiv said was the biggest drone attack since the start of the invasion.
The Ukrainian army said Russia had launched a "record number" of Iranian-made Shahed drones, the majority of which were downed over the capital, Kyiv, causing power cuts in the centre of the city as temperatures dipped below freezing.
The drone attack came as Ukraine marked Holodomor Remembrance Day, commemorating the 1930s starvation of millions in Ukraine under Soviet dictator Joseph Stalin.
"The enemy launched a record number of attack drones at Ukraine! The main direction of the attack is Kyiv," the commander of Ukraine's air force, General Mykola Oleshchuk, said.
The air force said it had downed "74 out of 75" Shahed drones.
Kyiv authorities said five people - including an 11-year-old child - were wounded in the capital, where the air raid lasted six hours.
Falling drone debris had sparked fires and damaged buildings across the city, Kyiv Mayor Vitali Klitschko said.
AFP saw Kyiv residents clearing smashed windows and other damage in the city's Dniprovsky district, with ambulances parked nearby.
One of the buildings that was damaged housed a nursery and another had part of its top floor destroyed.
Local resident Viktor Vasylenko said he had soothed his young daughter, who experienced "panic and nausea" during the long night-time attacks as they sheltered in a corridor.
The 38-year-old said his family always has "everything prepared" in case of such attacks but it was the first time one had hit so close.
"My wife thought that the house would collapse in half," he said.
Latvia's president, Edgars Rinkevics, on a visit to Kyiv during the attack, posted a photo of himself on social media inside a dark bomb shelter.
Dozens of buildings had their power cut off after the attacks but Ukraine's energy ministry said electricity was later restored.
Kyiv's army said that while the "main target" of the attack was Kyiv, air defence had also been called into action across southern Ukraine and a guided missile had been destroyed over the central Dnipropetrovsk region.
There were power cuts across the region, authorities said.
Kyiv has warned of and prepared for a renewed Russian campaign targeting its energy grid as winter descends, fearing a repeat of events last year, when thousands were left without heat or light in freezing temperatures.
More than 21 months into Moscow's offensive, fighting is most intense in the east of Ukraine and is now centred around the city of Avdiivka, which is nearly encircled by Russian forces.
Kyiv authorities said it was "symbolic" that the capital had been the subject of such a large-scale attack on the day Ukraine marks Holodomor.
"More than 70 Shahed on the night of the Holodomor Remembrance Day... The Russian leadership is proud of the fact that it can kill," Mr Zelensky said on social media.
Mr Zelensky attended a ceremony with Kyiv's top military brass, holding candles, to mark the event.
"We mark the solemn anniversary of the Holodomor as the brave people of Ukraine continue to defend their freedom and Ukraine's sovereignty against Russia's brutal war of aggression", US President Joe Biden said in a statement.
"Ninety years ago, the inhumane polices of Joseph Stalin and the Soviet regime created the 'death by hunger'," he said.
"Today, Ukraine's agricultural infrastructure is once more being deliberately targeted this time by Vladimir Putin as part of his drive for conquest and power."
Ukraine says Holodomor - Ukrainian for "death by starvation" - was caused deliberately by Soviet's agricultural policies.
Moscow denies this, and says it was part of a wider famine that also affected Russian parts of the Soviet Union.
Mr Zelensky said it was "impossible" for Kyiv to forgive or forget the "horrific crimes of genocide" and thanked the growing number of countries that had recognised Holodomor as a deliberate crime against Ukraine.
"They tried to subjugate us, to kill us, to exterminate us," Mr Zelensky said. "They failed".
Mr Zelensky said Russia's current attacks on Ukraine were possible because of what he called uncondemned crimes of the past.
"In the last century, famine came from Moscow. Now, we hear words of denial from there. And every one of these words of denial actually sounds like a confession," Mr Zelensky said.
Switzerland's President Alain Berset was in Kyiv today and paid homage to the victims of Holodomor that he said was "provoked by Soviet leaders".
The pair discussed "humanitarian demining, the use of frozen profits from the assets of the aggressor country and the peace formula", according to Mr Zelensky.
Switzerland's famous tradition of neutrality has been tested since Russia invaded Ukraine the Alpine country has followed the EU's lead on sanctions on Moscow but has refused to allow countries that hold Swiss-made weapons to send them to Kyiv.
Kyiv has set up a new corridor in the Black Sea since Moscow pulled out of the UN-brokered grain deal in July, but it continues to operate under risk.
Ukraine has urged the West for more weapons to counter the Russian invasion, concerned that global attention has shifted to the Israel-Gaza conflict.
Drones have been extensively used in the conflict, with Ukraine also launching drones into Russia and annexed Crimea.
In Moscow, Russia's top state television presenters took part in a ceremony bidding farewell to war correspondent Boris Maksudov, who was killed by a Ukrainian drone in Russian-occupied southern Ukraine earlier this week.
Russia said he had sustained injuries in the Zaporizhzhia region on Wednesday and announced his death the next day.
Vladimir Putin awarded Mr Maksudov a courage award posthumously, according to a decree published today.
