A shocking drone video appears to show 'the moment Russian troops committed the mass execution of 16 Ukrainian prisoners of war'.
It is the largest known massacre of this kind during the brutal conflict which has lasted more than two-and-a-half years, if verified.
Ukraine alleges the footage shows that the soldiers are acting on a murderous policy of the Putin regime authorising the killing of POWs.
The 16 surrendering soldiers are seen emerging from woodland under Russian control near Pokrovsk in Donetsk region.
The POWs line up in formation in an open space and then four of Vladimir Putin's troops appear to open fire on them.
Dmytro Lubinets, the Ukrainian parliament's commissioner for human rights, stated that he sent letters to the UN and the International Committee of the Red Cross regarding the apparent massacre
Ukrainian prosecutor-general Andriy Kostin said an investigation has been initiated into another war crime by the Russian army
The 16 surrendering soldiers are seen emerging from woodland under Russian control near Pokrovsk in Donetsk region
Those who still showed signs of life were 'finished off' at short range by automatic weapons, alleged the Ukrainians.
The Russians then run back into the forest plantation which appears covered in fog or smoke.
'An investigation has been initiated into another war crime by the Russian army,' said Ukrainian prosecutor-general Andriy Kostin.
'This is the most massive known case of the execution of Ukrainian prisoners of war on the front line.
'It is further evidence that the murders and torture of prisoners are not an accident, but a purposeful policy of the Russian military and political leadership.'
The SBU security service of Ukraine is working to 'verify' the footage which appeared on Telegram channels.
'Investigative and search activities have been launched to establish all the circumstances of the specified crime,' said Kostin.
The execution of POWs is a 'cynical and gross violation of the Geneva Conventions'.
Dmytro Lubinets, the Ukrainian parliament's commissioner for human rights, stated that he had already sent letters to the UN and the International Committee of the Red Cross regarding the apparent massacre.
'The systematic crimes against Ukrainian prisoners of war must be stopped, and those responsible must be held accountable,' he said.
A succession of videos have highlighted the alleged killing of surrendering Ukrainian troops.
'The inhumane country has once again violated international humanitarian law and the Geneva Conventions, resorting to new scales of executions of POWs,' said Lubinets.
The POWs line up in formation in an open space and then four of Vladimir Putin's troops appear to open fire on them
Any Ukrainian soldiers who still showed signs of life were 'finished off' at short range by automatic weapons, alleged the Ukrainians.
The Russians then run back into the forest plantation which appears covered in fog or smoke
