Russian military personnel killed five unarmed Ukrainian prisoners of war last month, the Donetsk Region Prosecutor's Office reported on Friday.
The prosecutor's office said that Russian troops stormed Ukrainian positions near the city of Vuhledar, in Donetsk Oblast, during an offensive in which five defenders were captured on October 2.
Citing operational data, it said one was killed in a forest belt, while four were taken to the road at gunpoint, where they too were shot.
"The killing of prisoners of war is a gross violation of the Geneva Conventions and qualifies as a serious international crime," the report said.
It added that investigative actions are being carried out to establish the full circumstances of the incident, with the pre-trial investigation being carried out by the Main Directorate of the Security Service of Ukraine in Donetsk and Luhansk regions.
Newsweek has contacted the Russian defense ministry for comment via email on Saturday outside of standard working hours.
On Saturday, Lieutenant General Kyrylo Budanov said Kyiv is aware of Russian "execution lists" targeting Ukrainian teachers, journalists, priests, and others.
"[The execution lists] were supposed to include teachers of the Ukrainian language, literature, history, ATO [Anti-Terrorist Operation] veterans, journalists, scientists, writers, priests of the Orthodox Church of Ukraine and other denominations who supported Ukraine, public and political figures, heads of state authorities and self-government," said Budanov.
The intelligence head also said that "Ukrainophobia" has affected the entire society of Russia.
"The genocide of Ukrainians is not only the state policy of the Russian Federation, but also a mandatory social conviction from above," he said.
Moscow launched a hypersonic missile strike this week on the central Ukrainian city of Dnipro, targeting a military facility.
The attack utilized the experimental Oreshnik hypersonic missile, an intermediate-range weapon that can reportedly be equipped with either nuclear or conventional warheads.
In a televised address, Russian President Vladimir Putin said the strike was a response to Ukraine's deployment of U.S. and British long-range missiles, which have been used to target sites within Russia. "No one in the world has weapons like these," Putin said.
President Joe Biden greenlit the use of U.S.-supplied Army Tactical Missile Systems (ATACMS) for strikes inside Russian territory in a significant policy shift announced last weekend.
Biden justified the move as a response to the involvement of North Korean troops in the conflict.
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