Heavy fighting in the Democratic Republic of Congo is again threatening the region's critically endangered mountain gorillas, conservationists have said.
For three months rangers funded by Wildlife Direct have been unable to enter the gorilla zone in the Virunga National Park in the east of the country because of clashes between 20,000 Congolese soldiers and the 4,000-strong forces of ex-general Laurent Nkunda.
The 70 park rangers in the area are among around half a million people who have been internally displaced in the violence, according to the United Nations.
"In the 34 years I have been a ranger this is one of the most trying and exasperating moments," said Norbert Mushenzi, an official with the Congolese Institute for the Conservation of Nature. "We have been totally unable to do our job due to the senseless fighting."
Wildlife Direct said that heavy shelling and gunfire were a severe threat to the animal. Its director, Emmanuel de Merode, said that despite their natural shyness, gorillas habituated to humans were not known to flee the sounds of war.
"I think it's unlikely that they would move away," he said. "The situation is absolutely chaotic. There is a war going on around the mountain gorillas. We need the fighting to stop, and we need to know about the welfare of these animals. We have no real data on what's going on."
Lucy Fauveau of the Zoological Society of London said: "The security situation in North Kivu is escalating. It is simply impossible to enter the Gorilla Sector. At this point, we need to provide humanitarian assistance to the rangers who are in the worse-hit sectors."
The fighting was triggered by the breakdown of a ceasefire with Nkunda, who says he is protecting the area's Tutsi ethnic minority, It has raised fears of a return to all-out conflict in the country, where four million people died as a result of the war between 1998 and 2003.
It comes on top of what was already the worst year on record for gorilla conservation in the region. At least 10 gorillas have been killed, two in January for bush meat, allegedly by some of Nkunda's troops, and eight in June and July.
"It's an absolute catastrophe for the conservation effort in Congo," said Dr de Merode, who blamed the summer killings on interests in the local charcoal industry, which is worth an estimated £15 million a year.
"The people behind the charcoal industry have seen the effort to protect the gorillas as a threat to their trade," he said. "It comes down to the simple logic that the forest is protected for the gorillas, so by killing them they are gaining access to the forest for charcoal."