The charcoal cutters of Virunga National Park know that their trade is illegal. Their fires, where they turn freshly cut olea trees into blackened cooking fuel, are built far from prying eyes in the war zone.

The illegal trade in charcoal has cut a strip of savannah through the Democratic Republic of Congo’s tropical rainforest, threatening the survival of the park’s rare mountain gorillas. Now the industry, worth £20 million a year, is having an equally devastating effect on human populations as the battle for control of the region’s rich natural resources fans the flames of civil war.

The forest close to Rubare is home to Rwandan Hutu militias, who fled their homeland after Tutsi rebels took power in 1994. Today they are known as the Democratic Forces for the Liberation of Rwanda. Back then they were the death squads of the Interahamwe – meaning “those who work together” – responsible for killing hundreds of thousands of Tutsis and moderate Hutus.

One of the cutters, Mumbere Ambrose, used a machete to hack some branches into a convenient size for charcoal as a chainsaw buzzed close by. To get access to the best trees, Mr Ambrose is forced to give money to the Hutu militias, who hold much of the southern reaches of Virunga, skimming cash from the charcoal producers to fund their war. Elsewhere, countless rebel factions are vying for control of other natural resources – among them gold.

In recent weeks forces loyal to General Laurent Nkunda, who claims to be protecting local Tutsis from Hutu militiamen, have moved to within six miles of Goma, the regional capital. About 250,000 people have been displaced as the renegade commander continues his offensive.

General Nkunda blames the Congolese Army and the UN for the war, but suspicions remain that he is backed by Rwanda, which wants a share of Congo’s mineral fields. The irony is that peace in a land of such rich mineral resources would bring prosperity to people who, on average, survive on far less than a pound a day.

For now, the charcoal cutters say that they have no alternative but to pay the levy to rebel groups and government soldiers. The road from Virunga into Goma is filled with young boys pushing wooden scooters piled high with sacks of charcoal, which sell for about £16.

At every stage government soldiers are also eager to take a share of the profits. “We don’t get through the barriers without paying something small,” said one boy as he laboured up a hill with his precious load.

Samantha Newport, a spokeswoman for Virunga National Park, said that the charcoal industry was the biggest threat to the forest and its endangered species. “The density of population and the deforestation outside the park means the park is exposed to thousands and thousands of people who need charcoal to survive,” she said. “The challenge is to find a solution before the park no longer exists.”

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