Indian authorities are investigating a large-scale illegal organ transplant ring that involves removing kidneys from poor people and selling them to rich Indians and foreigners. Anjana Pasricha reports from New Delhi that a thriving illegal trade in human kidneys has existed in India for at least a decade.

Few suspected what had been going on in a number of nursing homes and residential apartments in Gurgaon, a posh Delhi suburb, until police broke up an illegal kidney racket there.

Police say over the last decade, a group of doctors operating out of Gurgaon removed kidneys from at least 500 poor migrants and sold them to wealthy clients - both Indians and foreigners.

Initial investigations show the laborers received about $1,250 for their kidneys. The organs were re-sold for up to $50,000. The network involved a group of doctors, nurses, pathology clinics and hospitals.

While this is the most extensive ring of its kind to come to light in India, it is not the only one.

India outlawed trade in human organs in 1994. Kidney transplants are allowed only if the organ is donated by a blood relative or a spouse.

But several cases have been exposed in recent years of doctors selling kidneys taken from poor people.

The editor of the Indian Journal of Medical Ethics, Doctor George Thomas, says the illegal kidney trade is fueled by rampant poverty and a long line of patients seeking transplants.

"There is very little regulation of what is going on in medical care in India, and when there is a situation where both patient and the donor, both think they have something to gain, then there is very little chance of anything going wrong when they undertake the activity of removing the kidney without legal sanction," he said. "The problem is that on the one side there is tremendous poverty, on the other side desperation on the part of people who need the organ."

In the Gurgaon case, most donors said they had been forced to have their kidneys removed. Some said they were lured to the city from smaller towns by promises of jobs then whisked away to guarded homes, where the operations took place.

Experts, however, say the likelihood is that these poor people sold their organs, but will not admit to it for fear of prosecution.

The modus operandi (operational method) of the trade is simple. Touts and middlemen scout small towns and city slums, and lure people in need of money.

Apparently finding poor organ donors is not difficult. The southern city of Chennai, which suffered major damage from the 2004 Indian Ocean tsunami, has the reputation of being a major hub for kidney trafficking. A study conducted by the anti-poverty organization Action Aid showed how widespread the practice is there.

Action Aid's Annie Thomas says the group found that as many as 36 people among the 2000 families housed in just one resettlement colony had sold their kidneys. She says they were victims of the tsunami, and had a pressing need for money.

"Their livelihoods they had lost, and whatever they had, their earnings or their belongings, they had lost. They had already taken some money from moneylenders, or they had some health issues," she explained. 

Doctors say that the kidney trade can only be curbed by increasing the number of legal donors to bridge the gap between demand and supply. An estimated 100,000 Indians are diagnosed with renal (kidney) failure every year - mainly due to the high number of people suffering from diabetes and high blood pressure.

A kidney transplant surgeon, Sunil Shroff, has founded the non-profit Multi Organ Harvesting Aid Network, a group that promotes organ donation.

He says that at the moment, only one body per two million people is donated for organ transplants - far fewer than in most other countries.

"We have a very low donation rate because there is no awareness about this program in this country, so what it means is we have a lot of brain-dead patients who could be potential donors," he said. "We need to push up this rate of donation."

Until that happens, the combination of unscrupulous doctors and teeming slums will continue to supply the illegal kidney trade.