Lava flowing from a volcanic eruption in eastern DR Congo was gathering pace and set to destroy up to 10 hectares (25 acres) of forest in Virunga National Park by late Sunday, vulcanologists said.
The Goma Vulcanological Observatory, which has been monitoring the eruption of nearby Mount Nyamulagira early Saturday, said the pace of destruction would increase as it hit steeper ground.
"From Monday, the speed will increase because the territory starts to slope whereas it had been flatlands before," the observatory's director Karume Katcho told AFP.
He said a 15 metre-wide swathe of lava "is burning the forest. We estimate that up to 10 hectares (25 acres) of the area will be burnt after today."
Officials said the eruption was concentrated in a sparsely populated area, though wildlife habitats were under threat.
The volcano stands 22 kilometres (14 miles) from the provincial capital Goma, which it last threatened in 2006.
Virunga National Park is a UNESCO World Heritage Site and located on a chain of active volcanoes including Nyamulagira. It is home to around 200 of the world's last 750 mountain gorillas, but these are located further east of the volcano near the border with Rwanda.
The national park also contains large numbers other species, including elephants, hippopotamus and buffalo..
The ash and volcanic fibres from the eruption are harmful to animals as they can pierce their stomachs and intestines, but so far the chimpanzee population in the risk zone has not been affected, wildlife officials said..
Explore further: Historic climate data provided by Mediterranean seabed sediments