UK police on Friday said they have received "around 50" referrals relating to alleged war crimes linked to the Ukraine conflict in support of the International Criminal Court investigation.
Referrals have been received from across the whole of the UK, and mostly relate to what appears to be attacks against civilians since Russia invaded Ukraine in February, said the Metropolitan Police's War Crimes Team, which is part of the Counter Terrorism Command.
"Since the start of the recent military activity in February, our officers have been proactively engaging with Ukrainian communities in the UK," said Dominic Murphy, head of operations for the Met's Counter Terrorism Command.
"We've had around 50 referrals... and we expect that number to grow over the coming weeks as more and more people who fled from Ukraine arrive here in the UK.
"I'd also ask any households across the country who have volunteered to host Ukrainian people that should you come into contact with anyone who might have been witness to, or victim of possible war crimes, then you encourage them to contact us."
The War Crimes Team is responsible for carrying out any UK enquiries into war crimes and is appealing for anyone who may have direct evidence of violations in Ukraine from November 2013 to present to come forward.
Evidence gathered by the unit may then be shared with the ICC to assist with their ongoing investigation.
The War Crimes Team launched an appeal for information on March 4, soon after the ICC's chief prosecutor announced an "active" investigation into possible war crimes in Ukraine.
Digital signs have been put up at UK airports, railway stations and ports asking for anyone who "may have witnessed or been a victim of any possible war crimes or crimes against humanity" to contact police.
Police have asked for photographic or video evidence to be handed over, dating back to November 21, 2013 and the run-up to Russia's annexation of Crimea.