Surrendering LTTE fighters and their families were detained, tortured and shot, the trooper said. Channel 4 also interviewed in the studio the former Chief Prosecutor for the International Criminal Tribunals for the former Yugoslavia and for Rwanda, Louis Arbour, who slammed the impunity enjoyed by Sri Lankan forces throughout the armed conflict. Sri Lanka’s ambassador to the United Nations, Palitha Kohana, failed to show up, despite agreeing beforehand to appear to defend his government’s record.

The senior Sri Lankan army commander said: "I don't think we wanted to keep any hardcore elements, so they were done away with. It is clear that such orders were, in fact, received from the top."

"Definitely, the order would have been to kill everybody and finish them off,” he said. “It is clear such orders would have been received from the top.”

Tthe Sri Lankan trooper said: “Our commander ordered us to kill everyone. We killed everyone.”

He confirmed he killed civilians. Surrendering LTTE fighters and their families were detained and tortured before being shot, the soldier also said.

Channel 4 News broadcast several photographs taken by soldiers from the killing fields in Northeastern Sri Lanka, showing piles of bodies, lines of corpses and terrified civilians. Some of the bodies had their hands tied behind their backs.

The program quoted soldiers’ as saying LTTE leader Pirapaharan’s thirteen year old son had also been shot dead after surrendering with his bodyguards.

Speaking on the Channel 4’s flagship news program at 7pm, Louis Arbour said there was no possibility of Sri Lanka holding a proper inquiry into the war crimes, noting that since the conflict began there had been impunity.

She questioned the viability of the Sri Lankan government investigating the conduct of its own armed forces.

A senior Amnesty International official told Channel 4 News his organisation had this week launched a world-wide campaign to highlight the need for an independent international investigation into war crimes in Sri Lanka.

London-based Amnesty International and New York-based Human Rights Watch have joined Brussels-based International Crisis Group in this regard, Channel 4 said.

This week International Crisis Group, of which Arbour is currently head, released a detailed account of the mass slaughter during the final months of the conflict last year. The report said “the scale of death was much higher than reported at the time, and certainly high enough to triple the UN’s internal figure of 7,000.”

Noting that both the LTTE and the Sri Lankan armed forces were responsible for war crimes, the report made clear that “all but a small portion of these deaths were due to government fire”

“Eventually, an independent and impartial survey of those still living in the Northern Province will be needed to establish this part of Sri Lanka’s history,” ICG said.

On Monday night Arbour told an audience at Chatham House – the foreign policy think tank – that "the [Sri Lankan] government's refusal to distinguish between combatants and non-combatants" and the "sheer magnitude of civilian death and suffering" dealt what she called "the most serious of body blows to international humanitarian law".

Despite Channel 4 ‘desperately’ trying to locate him, Sri Lanka’s ambassador to the United Nations, Palitha Kohana, failed to show up, despite agreeing beforehand to appear to defend his government’s record, news anchor Jon Snow said.

Sri Lanka’s London High Commission meanwhile issued a statement totally denying the allegations of war crimes.

“The High Commission of Sri Lanka in the United Kingdom totally deny the allegations made against the Government of Sri Lanka and its armed forces. As it has been repeatedly stressed and supported by evidence, Government’s security forces were engaged in a humanitarian operation with the objective of rescuing the civilians held as human shields by a terrorist outfit: the LTTE, which was banned in many countries including the UK,” the statement said.

“All internationally accepted standards and norms of such operations were followed in the prosecution of the humanitarian operation by the security forces which were under strict orders to follow a zero civilian casualty policy.”

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