Drones attacked the Ukrainian capital early Monday morning, the Kyiv city military administration said, urging people to heed air alerts.
"The enemy is attacking the capital," the administration posted on Telegram.
"At the moment, 9 enemy UAVs (unmanned aerial vehicles) have already been shot down in the airspace of Kyiv."
It added that the Russian forces were using barrage ammunition from "Shaheds", Iran-made weapons that have pummelled the capital in recent weeks.
The city's civil administration announced an initial air alert at 1:56 am (2356 GMT) which lasted for just over three hours. A second siren at 5:24 am (0324 GMT) was called off within a half hour.
Kyiv mayor Vitali Klitschko confirmed on Monday that "explosions" had occurred in the capital.
"Several explosions were heard in the Solomianskyi and Shevchenkivskyi districts of the capital," he said. "All services work on the ground. More details later."
Ukraine has been subjected to frequent and deadly aerial attacks in the 10 months since Russia's invasion in February.
After a series of key battlefield setbacks and lost territory this summer and autumn, Moscow pivoted strategies and stepped up its aerial campaign.
Russia's defence ministry says its strikes are targeting Ukraine's military and energy facilities, while also disrupting "the transfer of weapons and ammunition of foreign production".
'Barbaric' bombings
But with temperatures dropping, the missile and drone attacks have plunged cities around the country into darkness, and severed water and heat supplies to millions of Ukrainians.
France and the European Union have said Russia's assault on civilian infrastructure constitutes war crimes, with the bloc's foreign policy chief calling the bombings "barbaric".
After a major assault on multiple cities involving more than 70 missiles on Friday, the national electricity operator was forced to impose emergency rolling blackouts as it raced to repair the battered energy grid.
In the capital, people had bundled into metro stations seeking heat and shelter while officials scrambled to restore power.
Ukrainian President Volodymyr Zelensky said as of Sunday night, nine million people have had their energy restored.
"In most cities, the work of transport is being normalised," he said in his nightly address.
Last week, Ukraine's Western allies pledged an additional 1 billion euros in emergency winter aid for Ukraine
Zelensky had said the high sum was needed to secure spare parts for repairs, high-capacity generators, extra gas and increased electricity imports.
Meanwhile, Russian President Vladimir Putin has sought proposals from his top military brass on how to proceed with the invasion. He asked for "short- and medium-term" plans in footage broadcast on state TV.
Ukrainian military leaders have warned that Moscow is gearing up for a major winter offensive, including an attempt to seize Kyiv.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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