A day after Russia accused Ukraine of carrying out a drone attack on the Kremlin, explosions were heard in Kyiv and other Ukrainian cities.
The air strikes occurred as Ukrainian President Volodymyr Zelensky prepared to speak in The Hague as part of an unplanned visit to the Netherlands.
Russia has accused Ukraine of attempting to assassinate President Vladimir Putin, but Mr Zelensky denied that his country carried out the attack.
Mr 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, Mr Zelensky met with Dutch Prime Minister Mark Rutte.
Russian airstrikes in Ukraine’s Southern Kherson area killed 21 people on Wednesday, according to officials.
The victims included store customers and energy company workers who were doing repairs.
In the early hours of Thursday morning, air raid sirens rang out across many Ukrainian regions. Loud blasts were reported in Kyiv and Odesa.
At the same time, a drone hit an oil refinery in southern Russia, setting part of it on fire – the latest in a series of explosions, fires and drone attacks that have occurred in Russia in recent weeks.
