Two British citizens have been kidnapped in the Democratic Republic of Congo, sources have said.
The pair are understood to have been abductedwhile visiting the Virunga National Park, a renowned gorilla sanctuary in the east of the African country, on Friday.
A female park ranger travelling with the pair was killed, according to local media reports.
The park has seen rising violence in recent months as armed groups stage raids to steal resources, particularly charcoal.
Last month five young rangers and a driver were killed in a militia ambush, the park said.
It was the deadliest attack in recent years and took the total number of rangers killed to 175.
Virunga is a Unesco world heritage site, covering 3,000 square miles on the Democratic Republic of Congos border with Uganda and Rwanda.
Founded in 1925, it is home to to around a quarter of the worlds critically endangered mountain gorillas and other endangered species as well as lions, elephants, hippos and a host of rare bird species.
Last year, a fifth of the parks southern sector was deforested owing to illegal charcoal production, the park said.
A Foreign Office spokesman said: We are in close contact with the authorities in Democratic Republic of the Congo following an incident involving two British nationals, and our staff are providing support to their families.