Bui Tien Luc, 37, Tran Thanh Hoa, 32, Nguyen Thanh Phong, 33, and Phan Thanh Hai, 27, are being investigated for "trading human body parts," the Binh Chanh District police said Tuesday.
Luc, a native of Ninh Binh Province in the north, was in need of money in 2017 and advertised online that he would sell one of his kidneys.
An unidentified man contacted him and offered to pay VND250 million. Luc came to HCMC for the deal, and there got acquainted with the other three men.
After a few years they decided to set up a kidney trading ring early last year.
They would follow potential kidney sellers on social media and offer to pay them VND260-400 million. Then they would look for patients in dire need of a new kidney or their families, and offer to sell them one for VND400 million-1.1 billion.
People selling their kidneys would be provided with food and accommodation by the ring while waiting for the kidney transplant.
To meet legal requirements, the gang would forge documents such as marriage and birth certificates and local government approvals for the transplant.
In just over one year they struck 28 deals successfully carried out 13 transplants, earning VND12 billion in the process.
Journalists from HCMC Law newspaper were the first to discover the ring from a clue left by a person who once sold a kidney. They then began to dig deep and collected evidence.
The police then expanded the investigation and have found sellers and buyers from all over the country.
More than five million people have chronic kidney disease in Vietnam, and 100,000 have to get dialysis daily, official data shows.
Social insurance only covers the cost of dialysis, and those who need a transplant have to pay for it.
Those with kidney failure have to register and wait in line for a legal donor, which normally takes months and even more due to a serious donor shortage.
This has caused many patients to gradually lose hope and turn to the black market.
In many cases, donors and receivers have no information about each other.
In Vietnam, organ donation is taboo since many believe one should die wholly prepared for the afterlife, meaning black market kidney transactions are not rare.
According to the police, kidney traffickers usually do 30-50 deals a year.