Three British nationals are currently being held in custody by the Taliban in Afghanistan, a humanitarian organisation has told the BBC.
Scott Richards from the Presidium Network named one of the men as Kevin Cornwell, 53, from Middlesbrough.
The Foreign Office said it was working hard to contact the men.
The Presidium Network is a UK-based non-profit organisation that provides support to communities in crisis, representing the needs of people affected by violence or poverty to international policy makers.
Mr Richards confirmed the organisation is representing Mr Cornwell, a paramedic who works for a charity, and the second unnamed man but not the third British national.
Mr Richards said while there were "no official charges as such", the two men's detention was understood to be over a weapon in a safe in Mr Cornwell's room, which he said was stored with a licence issued by the Afghan interior ministry.
"That license is missing," he said, adding: "But we have taken several statements from witnesses who have seen the licence and affirm its existence.
The third man is understood to be Miles Routledge, 23, from Birmingham, who was evacuated from Afghanistan by British Armed Forces in August 2021.