Russia launched around 120 missiles and 90 drones in a "massive" combined air strike on Ukraine's energy infrastructure, Ukrainian President Volodymyr Zelensky said on Sunday.
"The enemy's target was our energy infrastructure throughout Ukraine. Unfortunately, there is damage to objects from strikes and falling debris," he said in a statement on social media.
Blasts shook Ukraine's capital Kyiv and other cities while neighboring Poland scrambled its air force early on Sunday after the two countries said a Russian missile attack was under way.
"Due to the massive attack by the Russian Federation using cruise missiles, ballistic missiles and unmanned aerial vehicles on objects located, among others, in western Ukraine, Polish and allied aircraft have started operating in our airspace," the operational command of NATO member Poland's armed forces posted on X.
It said it had "activated all available forces and resources at his disposal, the on-duty fighter pairs were scrambled, and the ground-based air defense and radar reconnaissance systems reached the highest state of readiness."
Blasts were heard in Ukraine's southeastern city of Zaporizhzhia and the Black Sea port of Odesa, Reuters witnesses said, and Ukraine's air force issued air raid alerts for all of the country., although the scale of the attack was unclear.
The air force urged residents to take cover and said a number of missiles, including different types of cruise missile, were flying through Ukrainian air space.
Civilian impact
Ukrainian officials said they had cut power to a number of regions, including Kyiv, as a preventative step.
The missile attack followed an overnight drone strike on Ukraine's capital. The roof of a residential building caught fire due to falling debris and at least one person was injured, city officials said on the Telegram messaging app.
"Emergency services were dispatched to the scene," Kyiv's Mayor Vitali Klitschko said.
Ukraine has been on alert for weeks, fearing a major Russian missile attack as winter sets in. Previous attacks have targeted the power grid and caused sweeping blackouts.