Explosions have been heard in Kyiv and other Ukrainian cities, a day after Russia accused Ukraine of carrying out a drone attack on the Kremlin, reports BBC.
Attacks were also reported in Zaporizhzhia and Odesa in the south.
The air strikes come as Ukrainian President Volodymyr Zelensky is due to speak at The Hague as part of an unexpected visit to the Netherlands.
He will also visit the International Criminal Court, which is investigating alleged Russian war crimes in Ukraine.
Russia has accused Ukraine of attempting to assassinate President Vladimir Putin, but Zelensky denied that his country carried out the attack.
On Wednesday, he said: "We don't attack Putin or Moscow. We fight on our territory. We are defending our villages and cities."
Zelensky was speaking in Finland, where he made a surprise visit and met his Finnish counterpart Sauli Niinisto and the leaders of Sweden, Norway, Denmark and Iceland.
During his visit to the Netherlands, Zelensky is expected to meet Dutch Prime Minister Mark Rutte. Dutch media said that the two were likely to discuss Zelensky's demands for more military support - namely long-range weapons and fighter jets.
Bd-pratidin English/Golam Rosul
