Rwandans have been commemorating the 20th anniversary of the murder of gorilla conservationist Dian Fossey.
Dian Fossey inspired the film Gorillas in the Mist
The US researcher spent two decades working among Rwanda's rare mountain gorillas and was the subject of the Hollywood film Gorillas in the Mist.
Local people held traditional dances while government officials made speeches and laid wreaths where Ms Fossey was buried.
It has never been established who killed her in her jungle cabin in 1985.
The ceremonies were held in the Volcanoes National Park, where she had had her research base.
Rosette Rugumba, the director-general of Rwanda's Parks and Tourism Board, praised Ms Fossey's work.
"Fossey brought the plight of mountain gorillas to the attention of the world," she told Reuters news agency.
"She was dedicated to the conservation of gorillas and their habitats in Rwanda and Africa at large through anti-poaching, regular monitoring, research and education."
During a decade of conflict in the region, gorillas have become easy prey for armed poachers.
Only about 700 gorillas survive in the remote range of volcanoes spanning the borders of Rwanda, Uganda and the Democratic Republic of Congo.
Ms Rugumba said many thousands of tourists come to Rwanda each year to see the gorillas, where about a third of them live.
Ms Fossey's life inspired the 1988 film Gorillas in the Mist, starring actress Sigourney Weaver.