Nobel Peace Prize nominees David Matas and David Kilgour investigate the organ harvesting trade in China and uncover one of the world's worst crimes against humanity.

China is forcibly harvesting the organs of tens of thousands of political prisoners to operate a rapidly growing medical black market worth $1 billion a year, an international tribunal has found.

For several years, human rights groups have expressed concern many of the estimated 1.5 million people held in prison camps were part of an insidious human farming system.

But now, the specially formed China Tribunal in London has declared there is no doubt that state-sanctioned forced organ harvesting is occurring on a massive scale.

Made up of members from the United States, United Kingdom, Malaysia and Iran, including experts in human rights, transplant surgery and international relations, the independent tribunal heard from 50 witnesses and examined an enormous volume of visual and text evidence over the past year.

That included testimony about the barbaric practices, including organ removal on live patients.

Dr Enver Tohti worked as a surgeon in China and was instructed to perform organ extractions on unwilling subjects.

“What I recall is with my scalpel, I tried to cut into his skin, there was blood to be seen,” Dr Tohti told the tribunal of one such live procedure. “That indicates that the heart was still beating … at the same time, he was trying to resist my insertion, but he was too weak.”

A map of hospitals in China that carry out organ transplants shows they are in proximity to known detention centres.

The number of operations performed, the incredibly short waiting lists for recipients and the expansion of facilities demonstrated “beyond a reasonable doubt” that “forced organ harvesting has been committed for years throughout China on a significant scale”, the report said.

Chaired by the esteemed Sir Geoffrey Nice QC, the tribunal heard most of the detainees murdered for their organs were political prisoners from the Falun Gong movement as well as ethnic Uyghurs.

The practice, which China continues to deny, constituted genocide and industrial-scale murder and torture, Sir Nice said.

“Forced organ harvesting is of unmatched wickedness, on a death-for-death basis, with the killings (from) mass crimes committed in the last century,” he said.

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The tribunal heard forced extractions had been taking place from at least 2001 onwards, although the practice likely began long before that.

An estimated 60,000 transplant operations had taken place each year over the past two decades, the bulk of which were done with organs from murdered prisoners, the tribunal found.

“In addition to years of imprisonment without fair trial, brutal living conditions, torture and the threat of death, survivors gave evidence about being subjected to physical examinations including blood tests, X-rays and ultrasounds,” the tribunal reported.

“Experts report that the only reasonable explanation for these examinations was to ensure that victims’ organs were healthy and fit for transplantation.”

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Black market organs sell for a significant amount, with a healthy liver fetching around $160,000.

David Kilgour, the former Canadian secretary of state, testified at the tribunal’s hearings in April and said China’s organ trade was growing.

“The evidence is overwhelming that this terrible trafficking in human organs is going on … and is increasing, in fact,” he said.

China has consistently denied forced organ harvesting occurs, although the tribunal noted its official position had changed repeatedly.

“In 2001, an official statement from a Chinese official claimed that the ‘major source of human organs comes from voluntary donations from Chinese citizens’,” the tribunal found.

“However, only four years later, the official statement shifted to claim that the majority of organs were sourced from death row prisoners who had given their consent.”

A growing number of figures in the world’s medical and academic communities have said the scale of the trade is such it cannot possibly be supported by voluntary and legal donations.

Although, Sir Nice pointed out the international community continued to turn a blind eye, with many universities and medical organisations “actively collaborating” with China on research and training.