"In response to the Kyiv regime's attempt to damage Russia's energy infrastructure, the armed forces of the Russian Federation launched a combined strike [...] against energy facilities and enterprises of the Ukrainian military-industrial complex," the Russian ministry said in a statement.

Moscow's statement came after Kyiv reported "massive" overnight strikes on its energy grid, which wounded six people, as Ukrainian officials warned of possible blackouts amid a "particularly difficult" situation in the country.

"The enemy does not give up on its plans to deprive Ukrainians of light. A new massive attack on our energy industry!" Ukrainian Energy Minister Herman Halushchenko wrote on the Telegram social media platform.

The strikes targeted electricity generation and transmission facilities in the eastern Poltava, central Kirovohrad, southern Zaporizhzhia, and western Lviv, Ivano-Frankivsk and Vinnytsia regions, Galushchenko said.

The southern city of Kherson was also "partially without electricity" due to "enemy attacks", the region's governor Oleksandr Prokudin said.

National electricity company Ukrenergo warned that "from 6:00 pm to 11:00 pm (local time), power outages are possible throughout Ukraine".

The company urged its customers to "use electricity sparingly" to cope with what it said was an "especially difficult" situation.

"The Russians launched another massive blow on thermal and hydroelectric power plants," the operator lamented, adding that it was the fifth large-scale attack on the energy grid since March 22.

The Ukrainian air force said it had shot down 39 of the 55 missiles fired by Russia, as well as 20 out of 21 drones.

Local authorities reported at least six people wounded in the overnight attacks: one in the southern Dnipropetrovsk region, two in Brovary, near Kyiv, and at least two more in the capital.

An eight-year-old child was also wounded in the central Kirovohrad region, regional governor Andriy Raikovych said on Telegram.

Three thermal power plants were "seriously damaged", according to DTEK, Ukraine's largest private investor in the energy sector.

The company said its facilities have been hit by about 180 strikes since the start of the war in February 2022, including five times in the past six weeks.

Russia has been targeting Ukraine's energy grid for months, causing significant damage and widespread power outages.

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