Ukraine's energy ministry said that the Russian military has pounded energy facilities in the Dnipropetrovsk region in eastern Ukraine and other areas late Friday to early Saturday, seriously damaging four power plants.

Meanwhile the Ukrainian military has launched attack on oil refineries in Russia.

Russian news agency Interfax reported that operations at an oil refinery in the country's Krasnodar region were partially suspended following the Ukrainian drone attack.

A Ukrainian media outlet quoted an intelligence source saying that the country's security service conducted the attack.

As Russia continues its military invasion of Ukraine, Russian independent news outlet Verstka reported Thursday that many violent crimes have been committed by soldiers who returned from the war in Ukraine.

It says that public information from news reports and trial records was tallied and that 55 murder cases, in which 76 people were killed, were carried out by such ex-soldiers during the past two years.

A private military company, Wagner Group, was said to have recruited prisoners to fight in the war against Ukraine, telling them that they would be pardoned if they fought for six months.

The report says that 44 of the murder victims were killed by pardoned ex-prisoner soldiers.

The news outlet says that the number of such crimes could be much higher.