The head of the Odessa regional administration, Maksym Marchenko, said on Saturday that a Russian missile had hit a critical infrastructure facility in the Ukrainian region of Odessa.

Although he mentioned that no casualties were reported in the attack, he did not specify exactly what infrastructure had been targeted.

"One of the missiles hit critical infrastructure, causing some damage," Marchenko said on Telegram.

Read more: Emergency blackout taking place in several Ukrainian regions

Since this morning, air warnings have been issued all across Ukraine. 

Explosions were reported in several locations including Odessa, Vinnytsia, Dnipropetrovsk, Kharkov, Ivano-Frankivsk, Lvov, Volyn, and other regions.

While the regions of Kiev, Vinnytsia, and Cherkasy implemented emergency blackouts, Kharkov was hit by a total power blackout following an explosion. 

According to Ukrainian utility DTEK, two thermal power plants were damaged in the attacks. One of them had been shut down.

The head of the Ukrainian Energy Ministry, German Galushchenko, announced that energy facilities in five regions of Ukraine and the Kiev-controlled part of Zaporozhye Region had been hit at once.

The official also said that there were blackouts in most regions and that "the next few days in the energy sector will be difficult."

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