General Laurent Nkunda is a contradiction. An urbane jungle-dweller; an evangelical Christian warlord; a cerebral military strategist who unleashes awful brutality; a tribal protector and father of six who recruits children into his ranks; a patriot who wages war and steals the resources of the Democratic Republic of Congo.

As ever, General Nkunda, 41, has been justifying his assaults by saying that he must protect minority ethnic Tutsis. This week his 4,000 well-trained, disciplined troops marched from their mountain strongholds past the volcanoes and villages of North Kivu before stopping a few miles from Goma, a dusty provincial town bloated with refugees. The national army fled in disarray and UN peacekeepers failed to halt his advance.

Tall and slim, General Nkunda sometimes dresses in smartly pressed camouflage fatigues with a beret and a gold-topped cane, at other times in warlord chic with dark sunglasses, cowboy hat and a badge emblazoned with the slogan “Rebels for Christ”.

He studied psychology before joining the rebel army of Paul Kagame, now the President of Rwanda, in 1993. Their close relationship endures, and many accuse Rwanda of backing General Nkunda's rebellion. Mr Kagame denies this - but he has the influence to rein in the general if he chooses to, and it is clear that Rwandan businessmen and politicians benefit from the general's control of a swath of the country.

In 1994 General Nkunda and Mr Kagame, fellow Tutsis, fought alongside each other to push the Hutu tribal militias responsible for Rwanda's genocide out of the country and into what was then neighbouring Zaire, which became Congo in 1997.

In the ensuing war General Nkunda became a senior rebel officer, helping to topple Zaire's President, Mobutu Sese Seko. As Rwanda, Uganda, Zimbabwe and Angola all joined in the fight and stripped the country of its resources - from gold and tin to cows and bushmeat — General Nkunda's reputation for ruthlessness grew.

In 2002 he brutally suppressed a mutiny in Kisangani, a key trading town formerly known as Stanleyville that sits on a broad bend in the Congo River. More than 160 people were executed, some bound and flung off a bridge into the river, earning him the nickname “The Butcher of Kisangani”.

A 2003 peace deal intended to end the war - which had already claimed three million lives — gave him the rank of general in the national army but the agreement failed to end the fighting. Millions have died from disease or starvation, hundreds of thousands have been raped, and tens of thousands of children have been recruited to fight.

General Nkunda refused to report to the capital, Kinshasa, blaming the Government for failing to disarm the remaining Hutu militias in the east of the country. In June 2004 his troops besieged and then overran the once-beautiful town of Bukavu on the southern shore of Lake Kivu. Declaring that he had to protect the town's Tutsi population from ethnic attacks, his troops launched their own pogrom, raping women and children, murdering civilians and looting homes and shops.

For these crimes an arrest warrant was issued in 2005 but despite the presence in the region of 17,000 UN troops, General Nkunda has for years run a chunk of North Kivu as a private fiefdom from his mountain stronghold in Rutshuru. In person he is softly spoken and switches easily between English, French, Swahili and Kinyarwanda. He has a tendency to refer to himself in the third person and says he admires Mahatma Gandhi and President Bush. For now General Nkunda has ordered his forces not to enter Goma but if he changes his mind there is little to stop them. Everyone knows what happened in Bukavu; Goma's civilian residents are rightly terrified.

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