Russia attacked Ukraine with a barrage of missiles Thursday, including ones that targeted the capital, Kyiv, as well as the city of Kharkiv.

Ukrainian presidential aide Miykhailo Podolyak tweeted that Russia launched at least 120 missiles “to destroy critical infrastructure and kill civilians en masse.”

The attack prompted air raid sirens across the country, and Ukrainian officials said air defense systems were able to knock down incoming missiles.

Kharkiv Mayor Ihor Terekhov reported explosions in his city and said authorities were determining what had been hit and whether there were any casualties.

Russia has repeatedly used missiles to target Ukrainian cities, including strikes that have destroyed critical infrastructure sites.

Ukrainian President Volodymyr Zelenskyy is advocating a 10-point peace plan that calls for Russia to recognize Ukraine’s territory and withdraw its troops.

The Kremlin reiterated its dismissal of the proposal Wednesday, doubling down on its stance that Ukraine must accept the annexation Russia claimed in September after referendums rejected by Ukraine and most other nations as shams. The four Ukrainian regions include Luhansk and Donetsk in the east, and Kherson and Zaporizhzhia in the south.

“There can be no peace plan for Ukraine that does not take into account today’s realities regarding Russian territory, with the entry of four regions into Russia,” Kremlin spokesperson Dmitry Peskov said Wednesday. “Plans that do not take these realities into account cannot be peaceful.”

Also on Wednesday, Zelenskyy addressed the Ukrainian parliament in a closed-door session, urging lawmakers to remain united against Russia’s aggression, while praising Ukrainians for leading the West to “find itself again.”

“Our national colors are today an international symbol of courage and indomitability of the whole world,” he said in his 45-minute speech, his last of the year.

“In any country, in any continent, when you see blue and yellow, you know it’s about freedom. About the people who did not surrender, who stood, who united the world, and which will win,” he said.

Zelenskyy said the world had seen that freedom can be triumphant through Ukraine’s gains on the battlefield, and he thanked Ukraine’s military.

Zelenskyy noted Ukraine has gained the release of 1,456 prisoners of war since Russia’s invasion 10 months ago. Russia is believed to have thousands of Ukrainian prisoners of war, though actual figures are not known.

Some material for this article came from The Associated Press, Reuters and Agence France-Presse.