The allegation comes after Ukrainian President Volodymyr Zelensky warned – without providing evidence – that Moscow was receiving more ballistic projectiles and troops from its ally Pyongyang.
Russia has turned to North Korea for support throughout its four-and-a-half-year invasion.
Earlier in the war, Pyongyang dispatched thousands of troops to help Russia fight back a Ukrainian counterattack into its western Kursk region.
And intelligence from the West, Kyiv and Seoul, has long accused North Korea of supplying weapons to Russia.
The southeastern city of Zaporizhzhia was worst hit in Russia's latest overnight barrage, with seven people killed and 24 wounded, local authorities said.
"The city was struck with North Korean ballistic missiles, Zircons, and guided aerial bombs. It was a vicious attack, calculated to inflict maximum damage specifically on civilian infrastructure," he said.
All seven killed were employees of the Zaporizhstal steel plant.
"The ballistic strike caught employees on their way to shelter immediately after the air alert was announced," the plant said in a statement, adding that "another 21 of our colleagues were wounded".
Three more people were killed by Russian drones and missiles in the neighbouring Dnipropetrovsk region, the local military administration said.
In the capital Kyiv, Zelensky said an infectious diseases hospital was hit, while strikes on the frontlines cities of Kherson and Kharkiv caused power outages.
A children's hospital in Kyiv was also hit, the health ministry said, posting photos of broken windows and debris in a courtyard.
"Children and medical staff were not harmed, as they were in a shelter at the time of the attack," the ministry said.
Russia's defence ministry said its forces "delivered a group strike with high-precision ground-based weapons, hitting military-industrial enterprises and transport-logistics centres in the cities of Kyiv and Zaporizhzhia".
Later on Tuesday, Russia attacked Ukraine's northeastern Sumy region with "four guided aerial bombs", killing a man who was driving past one of the targeted areas, regional governor Oleg Grygorov said on Telegram.
Another two people were killed during a daytime strike in the southern port region of Odesa, local authorities said.
Russia meanwhile said a civilian was killed in a drone strike in its Belgorod region, bordering Ukraine.
Zelensky's N. Korea warning
Zelensky has recently renewed his warnings of deepening military ties between Moscow and Pyongyang, while appealing for more Western air-defence supplies.
On Monday, he said that Russia had received "additional ballistic missiles from North Korea".
Over the weekend, he alleged "a decision has been made for 30,000 to 50,000 North Koreans to be deployed on the territory of Russia."
Kyiv has not explained how it obtained the figures and did not provide a timeframe for the deployment.
But Zelensky is urging allies in the Asia-Pacific to supply air defence to Kyiv in order to counter Pyongyang's capabilities.
Seoul said it was watching the situation "closely". In recent weeks, Russia has considerably stepped-up strikes with ballistic missiles
"Military cooperation between North Korea and Russia is an issue that directly affects our security and constitutes a violation of UN Security Council resolutions," a spokeswoman for South Korea's foreign ministry told AFP.
A senior researcher at the Korea Institute for National Unification think tank, Hong Min, said "the prospect of additional North Korean deployments is highly plausible, given Russia's growing demand for manpower as the war drags on."
Russia and North Korea signed a mutual defence pact in 2024, ahead of Pyongyang sending troops to help push Ukrainian forces out of Russia's Kursk region.
In recent weeks, Russia has considerably stepped-up strikes with ballistic missiles -- a fast and powerful weapon that is hard to intercept.
Dozens have been killed in Kyiv in the attacks.
Only the most advanced air defence, such as the US-made Patriot system, is capable of intercepting them.
Ukraine has been reporting an acute shortage of Patriot interceptors since the US-Israeli war against Iran began in February.
Kyiv has also boosted its own long-range drone strikes against Russia, hitting oil infrastructure and e-commerce warehouses in counterattacks it says are justified and designed to crimp Moscow's logistics and revenue sources.
The latest spiral of escalation has brought the civilian death toll in Ukraine to the highest since the war's first months in 2022, according to the United Nations.
(FRANCE 24 with AFP)



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