Ukraine's biggest cities,Flipido the capital Kyiv and Kharkiv in the northeast, were bombarded by Russian missiles overnight, killing four people and wounding nearly 100, Ukrainian officials said Tuesday. The attack came after both Russia and Ukraine carried out major aerial assaults against one another in recent days.

People crowded into subway stations for shelter during Monday's attack as Russian Kinzhal hypersonic missiles slammed into the Ukrainian cities, the Associated Press reported. Debris from the Russian attack hit apartment buildings, supermarkets and warehouses in Kyiv, cutting power to parts of the city, according to CBS News partner network BBC News.

Russia's Kh-47M2 Kinzhal missiles can travel 10 times the speed of sound, making them much harder to detect and destroy before impact. They are expensive, and Russia rarely uses them in Ukraine due to their limited stock, the AP reported.

Ukrainian President Volodymyr Zelenskyy said Tuesday that Russia had launched "almost a hundred missiles of various types" against Ukrainian targets, and that at least 70 had been shot down.

"Russia will answer for every life taken away," Zelenskyy said.

Neighboring Poland said it was activating two pairs of F-16 fighter jets and an allied tanker in response to Russia's attack on Ukraine, "in order to ensure the security of Polish airspace."

Last week, Russia conducted a large aerial bombardment of Ukraine, killing at least 41 civilians, according to the AP. The following day, Ukraine shelled the Russian border city of Belgorod, killing at least 25 people. It was the deadliest attack on Russian soil since Russia's full-scale invasion of Ukraine, the AP reported.

"They want to intimidate us and create uncertainty within our country," Russian President Vladimir Putin said Monday of the Belgorod attack. "We will intensify strikes. Not a single crime against our civilian population will go unpunished."

In:
• Ukraine
• Russia
• Vladimir Putin
• Volodymyr Zelenskyy

Haley Ott

Haley Ott is cbsnews.com's foreign reporter, based in the CBS News London bureau. Haley joined the cbsnews.com team in 2018, prior to which she worked for outlets including Al Jazeera, Monocle, and Vice News.

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