Waves of Russian drones attacked the Ukrainian capital Kyiv early on Sunday morning as attacks on infrastructure and energy targets continued into a second night.

The head of Kyiv's military administration, General Serhiy Popko, wrote on Telegram on Sunday that the city had been attacked "in waves from different directions."

The Ukrainian air force reported that 15 out of 20 Iranian-produced Shahed "kamikaze" drones had been shot down over the Kyiv region, as well as near the cities of Poltava and Cherkasy to the south-east of the capital.

"No casualties or critical destruction were recorded," according to Popko.

Zelenskyy calls for 100% air defense effectiveness

The attacks came 24 hours after a similar assault on Saturday morning, when Ukrainian air defenses shot down 29 out of 38 drones launched from Russian territory. All Kyiv-bound drones were intercepted, but a successful strike in Odesa wounded a civilian, while power cuts were reported in over 400 locations.

Speaking in his daily address on Saturday evening, Ukrainian President Volodymyr Zelenskyy said Ukraine was boosting its air defenses ahead of an expected second winter of Russian air assaults.

"The closer we get to winter, the greater Russia's efforts will be to step up its attacks," he said, calling on his forces to be "100 percent effective, despite all the difficulties, despite all the fatigue."

Last winter, Russia fired hundreds of rockets and drones at energy and infrastructure targets across Ukraine, forcing the civilian population to endure cold nights without heating and electricity. The weather has remained unusually mild in Ukraine so far this year, but temperatures are starting to drop.

Ukrainian drone shot down over Moscow

In response, Ukraine also began launching smaller-scale drone attacks on targets inside Russia in summer, and did so again on Sunday morning.

"An attempt by the Kyiv regime to carry out a terrorist attack using a drone against facilities of the Russian Federation was thwarted," the Russian defense ministry said in a statement, saying the drone in question "was destroyed by air defense equipment ... over the territory of the Bogorodsky urban district in the Moscow region."

Moscow mayor Sergei Sobyanin later wrote on Telegram that the foiled attack "did not cause any damage or casualties" and that "emergency services were working on the site" where "the debris" from the device had fallen.

mf/lo (Reuters, AFP, dpa)