The air-raid sirens sounded at 15:40 local time (16:40 Moscow time) and are still going on, it follows from the online map data. Earlier on Saturday, air raid sirens were already sounding in these regions.
Recall that the Russian military has been attacking the critical infrastructure of Ukraine since October 10. In mid-December, the Ukrainian authorities announced damage to up to half of the energy infrastructure facilities. President Vladimir Zelensky spoke about the impossibility of a complete restoration of the power system. The Ukrainian Foreign Ministry does not rule out a complete power outage in the country.