KATHMANDU, Nepal (CNN) -- The alleged mastermind of a kidney transplant scheme in India has admitted to his involvement in about 300 transplants over the last 12 to 13 years, police said Friday.

Dr. Amit Kumar, smiling and with an apparent air of confidence, was paraded before reporters at the end of a news conference in which he declared his innocence.

"I have not duped anyone. I have not done anything wrong," Kumar said before authorities whisked him away. "You know that."

He was taken into custody Thursday evening in the Nepalese town of Saurah, about 95 miles (150 km) south of Kathmandu. Watch as doctor admits kidney transplants role »

Kumar was arrested by a special team of Kathmandu police and taken to a regional police station in Hetauda, Minister of State Ram Kumar Chaudhary said.

Amit Kumar is accused of coercing, stealing or buying kidneys from healthy Indians and then selling them to foreigners for transplant.

Several doctors have been accused of taking part in the scheme, Chaudhary said.

On Friday, authorities said Kumar will be charged in Nepal under the country's Foreign Exchange Regulation Act, which regulates the flow of international currency in the Asian nation. When arrested, Kumar was carrying approximately $256,000 in mixed currencies, including U.S. dollars, euros and a bank draft made out in Indian rupees.

Authorities in Nepal will also look into whether he violated the country's Human Organ Transplantation Act.

If convicted of a currency violation, Kumar could be imprisoned up to four years. An additional five years could come from a violation Nepal's transplant law.

Indian officials want him in connection with hundreds of kidney transplant cases. Since his arrest, India's Central Bureau of Investigation has contacted Nepalese officials requesting his extradition.

"We are investigating the case and will charge him according to the laws of Nepal," Upendra Kanta Aryal, the police official in-charge of the investigation, told CNN. "Only after that the legal process for extradition to India will begin."

Police in India have said that as many as 500 people may have each lost a kidney to the ring. Some told CNN they were forced to do so and not compensated.

A 2004 law limits organ donation and transplantation in India to blood relatives and close family friends. No money may exchange hands. E-mail to a friend

CNN's Sara Sidner and journalist Manesh Shrestha contributed to this story.

I seriously think indians and nepalese don't have ethics. Nepalese learn from indians. Without ethics and moral values, country cannot move forward. People will do anything to make money. It was in BBC and ABC news how the poor people of india were taken by some people in the middle of night to take out kidneys. These poor indians were told that they would get jobs instead they took in private clinic, took blood slamples and made them unconscious and took out kidney and left them in footpath. God where is humanity? Where is ethics?