Hundreds of thousands of people were massacred during the genocide of 1994 in Rwanda. Now, in the crucible of the ensuing war in neighbouring Congo, the fugitive killers are training their children to carry on the Hutu mission of extermination, and awaiting their opportunity to return to the mother country.

A number of the FDLR’s leadership were heavily involved in the Rwandan genocide. They include some who are wanted by the International Criminal Tribunal for Rwanda, which was set up by the UN Security Council to try those responsible for the massacres in Rwanda, and two men who are also on the US government’s "most wanted” list of those it wants to see captured and handed over to the tribunal.

Among the wanted FDLR leaders is Callixte Nzabonimana, the Rwandan minister of youth and sport during the genocide who, according to an international tribunal indictment, "played a major role in the massacres of the Tutsis in Gitarama.

He visited the bourgmestres [mayors] frequently to organise the massacres in their communes with them. Further, he personally travelled through the hills along with peasant farmers to be certain the farmers were carrying out properly their orders to kill the Tutsis”.

The US has offered a $5m (£2.5m) reward for his capture to be put on trial by the tribunal.

The tribunal has named another FDLR leader, Ildephonse Nizeyimana, as among its six most wanted.

He headed military intelligence operations in southern Rwanda and set up special units of soldiers that led massacres at the country’s main university.

He also gave the order for soldiers to surround a school as the interahamwe murdered 1,300 children and adults. The US is also offering a reward for Nizeyimana’s capture.

The FDLR’s overall military commander, Major General Sylvestre Mudacumura, is wanted by the Rwandan government to face trial for his role as deputy commander of the presidential guard which flew across the country to begin the mass murder in April 1994.

Today he is a primary mover behind the killing of Congo’s Tutsis. He is also under investigation by the international tribunal.

Among others listed as "most wanted” by the Rwandan government is an FDLR colonel, Faustin Sebuhura, who, as a captain in the Hutu army, oversaw the massacre of about 50,000 Tutsis, and Déogratias Hategekimana, who, as a mayor, coordinated the killing of 65,000 people.

The FDLR’s political leadership is less directly implicated in the genocide but is wanted in the Rwandan capital, Kigali, for atrocities against civilians by the rebel group.

While their organisation is also officially listed as a terrorist group by the US government, the rebels’ political chief, Ignace Murwanashyaka, lives largely untroubled in Bonn, Germany.

His deputy, Musoni Straton, is in Brussels. The FDLR also maintains some presence through representatives in other parts of Europe - France, Switzerland, Holland - and in South Africa, Canada and the US.

Talking now under the tree in Sange market, Ngarambe is evasive about his own part in the tragedy of 1994.

He was a Hutu army officer at the time. He denies the genocide was planned, even though the international tribunal for Rwanda has established that there was an extensive conspiracy at the highest political and military levels of the Hutu regime to exterminate the entire Tutsi population.

"If they say the genocide was organised, it’s not true. It was civil war. It was something that happened suddenly. It wasn’t planned,” he says.

"Ever since I was young, I didn’t know how to hate a Tutsi. I lived in a place with many Tutsis. My friends were Tutsis. Even in the army there was not teaching of hatred of Tutsis.”

But most of those Tutsi friends and neighbours are dead. It takes a while for Ngarambe to reveal that his own father is blamed for some of their killings. He is 75 years old and in a Rwandan prison awaiting trial for genocide.

In Sange market, the Congolese traders eye Ngarambe and his men warily. It is only after the FDLR officer has left that one or two will talk.

"We fear those men,” says a small woman in a yellow wrap selling vegetables from a basket.

"They use their guns to take our food and money. They do not leave us enough food for our own families but we cannot say anything because they will kill us.

There is no law here.” Others in the market decide it is wiser not to speak. Ngarambe concedes that his men take from the local people.

"When there’s a war, that’s when there’s difficulties. We are obliged to take food from the population when there’s fighting. But when we stay somewhere for six months, we try to farm,” he says.

"Our relations with the local population are extremely good. They understand our problems. They understand we will one day go back to Rwanda.”

In some places, Hutu refugees have built their own villages, including schools and health centres staffed by Rwandan teachers, doctors and nurses.

In others, they have moved into Congolese villages, sometimes usurping the authority of traditional chiefs and taking over administrative positions in local government.

Often they plunder crops - Congolese villagers have a saying about the FDLR: "We cultivate and they harvest” - and by extorting "taxes” from just about anyone, from market stall holders and farmers to transport companies and butcheries, and "tolls” to cross rivers and bridges. The FDLR also grows and sells significant amounts of marijuana.

Much of the FDLR’S money goes to buy weapons and to run the training camps, which include infantry and artillery schools, and one for the rebels’ commando unit that goes by the acronym CRAP.

But there is worse than plunder. Systematic rape of hundreds of thousands of women has been a hallmark of the conflict in eastern Congo, and the FDLR is not the only group involved.

In South Kivu alone, tens of thousands of women have been treated in health clinics after being raped, and many more will have gone untreated.

Ngarambe admits that some of his men are responsible but says everyone is at it, including a group known as the Rastas, made up of deserters from the notorious Mai-Mai militia, the Congolese army and the FDLR.

"This thing of rape - I can’t deny that happens. We are human beings. But it’s not just us,” he says. While the rank and file of the FDLR survives by plundering, their leaders are involved in altogether more lucrative ventures.

A 2007 World Bank-funded study estimates that the FDLR leadership makes millions of dollars a year from taking over mines in parts of North Kivu, such as Masisi and Walikale, or from those doing the hard labour through levying "taxes” of gold, coltan, diamonds and other minerals on mine owners.

The study estimates that the FDLR controls half of the mineral trade in the Kivus outside of the main towns, and oversees the smuggling of gold and diamonds for sale in neighbouring countries such as Uganda and Burundi.

The poison against Tutsis has spread beyond the Hutu exile population and infected many ordinary Congolese, largely driven by anger at the invasions of Congo by Rwanda’s government and at the actions of the renegade general Nkunda, who says he is fighting to protect Congo’s Tutsis from the FDLR.

From his headquarters in a colonial-era house in the hills around Masisi in North Kivu, Nkunda says he is an effect, not a cause, of Congo’s continued upheaval: "It’s as if you can kill Tutsis and no one cares,” he says.

"I am here to protect them and I won’t stop until the FDLR is gone, finished. We cannot allow it to take over North and South Kivu or all the Tutsis will be finished.”

"They say I’m the problem. But who is killing who? I am defending the Tutsis who live here from the people who committed genocide in Rwanda ... Remove the FDLR and you remove the need for me to fight.”

Many Tutsis see Nkunda as their only means of protection. Many Congolese see the Tutsis as the problem. Anti-Tutsi vitriol can be heard from Congo’s leaders down to the residents of eastern towns such as Goma.

Congolese politicians have called on people to "exterminate the vermin”, meaning Tutsis. Amid such entrenched hatred, the future for the boy in the oversize uniform is bleak.

Colonel Ngarambe has three children of his own now, the eldest just eight years old, all born in exile. He would like to see them settled in Rwanda but only on the terms he has in mind - a Rwanda where politics is defined by ethnic domination and the Tutsis recognise the rule of the Hutu majority. If not, Ngarambe says his children will carry on the fight.

"The children born here are FDLR,” he says.

"The children born in Rwanda will be FDLR. My children will be FDLR.

"The conflict between Hutu and Tutsi is based on power. It’s not that we have to develop an ideology of hatred against the Tutsis.

It’s just that people should see what’s happening. Just because the Tutsis were victims of a genocide doesn’t give them the right to take power.”

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