A doctor alleged to be the mastermind of an organ-trading racket in India has been arrested in Nepal, according to Nepalese officials.
Dr Kumar's clients were said to be wealthy Indians and foreigners
Amit Kumar was reportedly discovered in a jungle resort in southern Nepal.
India has asked Nepal to hand Mr Kumar over. He is expected to be questioned about a house in Delhi where illegal kidney transplants were carried out.
Officers say hundreds of poor labourers were lured from across northern India and bribed into selling their kidneys.
Kiran Gautam, the police chief in Chitwan district, about 160km (100 miles) south of Kathmandu, told Associated Press news agency Dr Kumar was being taken to the capital for questioning.
Nepal's minister of state for home affairs, Ram Kumar Chaudhary, told CNN that Dr Kumar was carrying $145,000 and a cheque for 900,000 euros ($1,305,000) when he was taken into custody.
According to Nepal's police, he could also face charges in that country relating to the foreign currency he was allegedly carrying.
Trade in human organs is banned in India but many continue to sell their kidneys to clients, including Westerners, waiting for transplants.
In January, police in Gurgaon, a suburb of Delhi, raided an illegal clinic after being tipped-off by a victim. Four people were arrested.
The donors were allegedly paid up to $2,500.
The clients are said to be wealthy Indians, and even some foreign visitors who were in urgent need of a kidney transplant and willing to pay large sums.