Air raid sirens went off in the Ukrainian regions of Nikolayev, Sumy, Poltava, Kharkov, Dnepropetrovsk, Kirovograd and Odessa at around 18:51 GMT on Saturday, the ministry’s online map showed.
Ukrainian broadcaster Suspilne reported later on Saturday that explosions were heard in Sumy. Several blasts also occurred in Kharkov, according to Ukrainian media reports.
At around midnight local time, air raid warnings were in effect in the regions of Sumy, Poltava, Kharkov, Dnepropetrovsk, Kirovograd.
Precision strikes against Ukrainian infrastructure have been carried out by Russia since October 10 (two days after the terrorist attack on the Crimean Bridge).
In February, the head of Ukrainian power grid operator Ukrenergo said that direct damage to Ukraine's energy infrastructure caused by Russian strikes may amount to hundreds of millions of dollars, with economic losses ranging in billions.