Russia launched a massive overnight missile and drone barrage across Ukraine, killing at least nine people and wounding dozens, officials said Tuesday.

In Kyiv, multiple explosions set off fires, killing three. Mayor Vitali Klitschko urged residents to stay in shelters as air defense systems engaged. Power was knocked out in several districts.

Separate attacks in Dnipro killed four, including a 73-year-old woman, and wounded 16, according to local governor Oleksandr Ganzha. In Kharkiv, eight people were wounded.

The strikes follow President Volodymyr Zelensky's warning that Russia was preparing a major new offensive. He renewed his call for allies to supply Patriot missile systems to counter ballistic missiles.

Ukraine retaliated with drone strikes, killing one in Russia's Kursk region.