Channel 4 News reports on the documentary Enemies of the People, in which former Khmer Rouge leader Nuon Chea expresses his regret for a time in which nearly two million Cambodians died.

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"I made mistakes, I have remorse, I am sorry." Those are the words of indicted Khmer Rouge leader Nuon Chea.

During his party's 44-month reign of terror in Cambodia in the 1970s he was known as Brother Number Two - second only to Pol Pot. Now that Brother Number One is dead, Nuon Chea holds all the secrets.

But he's refused to tell anything to the UN tribunal, where he'll go on trial next year. Instead he's revealed all to a Cambodian journalist, Thet Sambath. The result is a startling documentary based on hours of interviews, called Enemies of the People.

But its makers are refusing to hand over their material to the UN tribunal.

Former Khmer Rouge leader Nuon Chea, as seen in the documentary 'Enemies of the People'

"They were enemies of the people"

In the back room of a back alley house in provincial Cambodia, sits an old metal trunk. Inside it: 1,000 hours of audio tape and 160 hours of video; ten years' worth of interviews, conducted by Khmer journalist Thet Sambath.He wants answers to the one question that survivors of the Pol Pot time have long feared to ask. And the question is "why?"

His interviewee's in his 80s. He was Pol Pot's Number Two. In ten years, Sambath got to know Nuon Chea well. In the end, the old man confessed to how suspected traitors were purged, saying:

"They were killed and destroyed. If we had let them live the party line would have been hijacked. They were enemies of the people."

By the mid 1970s, half-a-million tonnes of American bombs, aimed at halting the advance of fanatical communism, had left half-a-million Cambodians dead, but the Khmer Rouge was an unstoppable force.

They were killed and destroyed. If we had let them live the party line would have been hijacked. They were enemies of the people." Nuon Chea, Brother Number Two

By they time they took power 35 years ago, Cambodia was a brutalised nation. In Enemies of the People, Thet Sambath narrates:

"There is only two at the top of the Khmer Rouge. "Pol Pot. They call him Brother Number One. And Nuon Chea, Brother Number Two."

Nuon Chea, Pol Pot's right hand man of the Khmer Rouge regime, sits in the dock during his first public appearance at ECCC in Phnom Penh 4 Feb 2008

They began their programme to return to the past: Year Zero. Cambodia became a vast workcamp, families were abolished; violent death employed a tool of social discipline. These were the Killing Fields, in which maybe two-million Cambodians died.

Nuon Chea told Thet Sambath that all this was what he called "the correct solution," but one day, he said something remarkable.

"I have always said I made mistakes. I am regretful and I have remorse. I am sorry for our regime. I am sorry." Nuon Chea, Brother Number Two

Channel 4 News interviewed a Cambodian survivor - Virak. The Khmer Rouge murdered three of her brothers. Her father ad two other brothers died of starvation in work camps. She said:

"I can never forgive for what Nuon Chea has done to all the Cambodian people.

"An estimated 1.7 m during the Pol Pot regime, and the people who are survive this Pol Pot time until now the scar of the genocide it never fade."

Tortured souls

The documentary also reveals the torment of those who actually did the killing at the orders of the regime.

In one section, a self-confessed peasant executioner, Soun, re-enacts with a plastic knife how they slit people's throats

Soun, with his fellow killer, Khoun, are today tortured souls, describing the desolation they feel, knowing what they have done.

I come back here to where I killed people. And I feel terrible. My mind, my soul, my body is spinning inside. Soun, Khmer Rouge killer

At a recent viewing of the film by Cambodian refugees in the United States, the two Khmer Rouge killers agreed to participate in a video conference with the American audience. The result was startling; it was as though those watching understood that Khoun and Soun were themselves victims; for them it was a release.

The most senior Khmer Rouge henchman, Comrade Duch, was sentenced to 35 years for crimes against humanity in July. He'd run a torture centre in Phnom Penh. He'd admitted to his role in killing and torturing thousands of men, women and children but said he'd only been following orders.

The orders were those of Pol Pot - now long dead - and Noun Chea, now an indicted genocidaire, due to stand trial next year.

But prosecutors have been unable to extract a confession and the UN Tribunal's tried to subpoena the trunkload of audio and video tapes as evidence, but the film-makers have refused.

One day, after nearly ten years, Thet Sambath, revealed something to Brother Number Two, that he'd kept secret all that time:

"Now I know your father, mother and brother were killed.

"I would like to say how deeply sorry I am."

Sambath admits to having felt better for telling him. It's never clear whether Brother Number Two feels any better for confessing and saying sorry.

But 30 years on from the Khmer Rouge reign of terror, it's this avuncular 84-year-old man who's the enemy of the Cambodian people.

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