Ukrainian President Volodymyr Zelenskyy on Wednesday condemned a video circulating online that the country’s security services said showed a Ukrainian being decapitated by “Russian occupiers.”
“There is something that no one the world can ignore,” Zelenskyy said in Ukrainian in a video posted to his Telegram channel.
“We are not going to forget anything,” he added. “There will be legal responsibility for everything.”
The video viewed by NBC News features a man repeatedly saying “it hurts” as another man wielding a small knife appears to saw into the man’s neck.
Another man then says to the one with the knife in Russian: “What, have you never chopped off a head before? Do it, do it, do it.”
Once the decapitation is finished, the knife-wielding man shows the dead man's head to the the camera.
What appears to be a Ukrainian identification document can be seen on the ground by the victim’s body while one attacker holds up a bulletproof vest with patches of the Ukrainian coat of arms and a skull.
NBC News was not able to independently verify the identity of the people in the video, its location or the date it was filmed.
Zelenskyy has described the victim as a “Ukrainian captive.”
The Security Service of Ukraine said the video showed “Russian occupiers … severely torturing a Ukrainian prisoner and cutting off his head.” NBC News has not been able to verify the allegation.
The Ukrainian government said it had started a war crime investigation after the video appeared on the internet on Tuesday.
When asked about the video on Wednesday, Kremlin spokesman Dmitry Peskov called it “horrifying.”
“In the world of fakes in which we live now, it is necessary to verify the authenticity of this video,” he added.
Yevgeny Prigozhin, the head of the Russia-based Wagner mercenary group, which has a large presence in Ukraine, said in a statement on his Telegram channel that he had seen the video but had not found that any of his fighters were “participating in the execution.”
Their comments came after Andriy Yermak, head of the Ukrainian presidential administration, questioned Russia’s presidency of the United Nations Security Council, which it assumed this month, on Telegram. The presidency rotates alphabetically each month among the 15 members.
Russia assumed the presidency after the International Criminal Court, which is not associated with the U.N., issued an arrest warrant last month for Russian President Vladimir Putin, accusing him of the war crime of illegally deporting hundreds of children from the Ukraine.
Russia, in turn, has accused Ukraine of war crimes, and the West of ignoring them.
In November, the Kremlin said that Ukrainian soldiers had executed more than 10 Russian prisoners of war. It has not provided any evidence of this or other claims.
The video that emerged Tuesday was the second apparent execution video to appear in just over a month. In March, graphic video circulated across social media showing what Kyiv’s military said was Russian forces killing an unarmed prisoner of war.
The 12-second video showed a man wearing what appeared to be a soldier’s camouflage uniform that bore a Ukrainian flag insignia, with a cigarette in his mouth.
After he quietly said, “Slava Ukraini” or “Glory to Ukraine,” gunfire could be heard almost immediately; the shooters were not shown. The man then crumples to the ground.
Ukraine’s military named the man as Tymofiy Mykolayovych Shadura. He was a member of the 30th separate mechanized brigade who had been missing around the city of Bakhmut in eastern Ukraine since early February, the army said in a Facebook post.
Kyiv has accused the Kremlin’s forces of committing atrocities throughout the war and urged international action to hold them to account. More than 74,500 such atrocities have been reported in Ukraine since Russia invaded, the prosecutor general’s office in Kyiv said last month.
Mass burial sites in the city of Mariupol as well as the the towns of Bucha and Izyum and are among the areas being investigated for possible war crimes.
Speaking at the Munich Security Conference in February, Vice President Kamala Harris said that Russia had committed “crimes against humanity” in its war against Ukraine, adding that “justice must be served.”