Two British aid workers have gone missing after reportedly being captured by Russian forces in Ukraine.
Presidium Network, a non-profit organisation, said the two workers were detained at a checkpoint south of the city of Zaporizhzhia.
The Foreign Office is urgently seeking more information on the claims.
“The Foreign Office is doing all it can to support and identify these two people,” Anne-Marie Trevelyan, the international trade secretary, told Sky News.
Both the Foreign Office and Presidium Network have been contacted for comment.
It comes after a British army veteran died while fighting Russian forces in Ukraine.
Scott Sibley - a father of two and believed to be 36 - is the first known UK casualty of the nine-week conflict.
Friends of Mr Sibley - who served in Afghanistan with the Royal Marines’ Logistic Support Squadron - have set up an appeal to pay for his funeral.
Mr Sibley, from Lincolnshire, was praised by ex-comrades.
One called him “a man that showed Commando spirit until the end. RIP. Scott Sibley”.
Former colleague Alex Darwin wrote: “Sib, I’m in complete disbelief. You were there for me and I will forever be grateful. One hell of a beautiful guy, inside and out.”
Earlier this month Britons Aiden Aslin, 28, and Shaun Pinner, 48, were captured and then paraded on Russian state TV asking to be swapped for a pro-Kremlin prisoner.
A small number of serving British personnel are believed to have gone absent without leave to join the resistance against the Russian invasion, while veterans and Britons without combat experience are thought to have also travelled to Ukraine.