“We are going to carry forward the investigation on the basis of these documents and other leads we might get from the raids carried out in Delhi and Faridabad earlier on Saturday,” Gurgaon Police Commissioner Mohinder Lal said.

“A number of documents and equipment were seized from the premises of two hospitals run by Amit Kumar, the main accused," Lal said. Faridabad Senior Superintendent of Police Alok Mittal said UP and Haryana police along with income tax sleuths sealed the premises of Sriram Hospital in Ballabhgarh, which was being run by Upendra Kumar and his wife Archana.

He said two MBBS degrees were seized from the hospital - one from Gwalior in 1983 earned by his wife and the other of Upendra Kumar from Moradabad, UP, in 1978. SSP Mittal said the husband-wife duo started running the hospital in 1999 “but he only goes there for a short period. He mostly used to operate from Gurgaon itself."

Police said foreigners and other kidney recipients needed medical care had been kept in a safe place to assist the investigation.

On queries about a car with diplomatic number plates visiting the DLF Phase I house where the racket was unearthed, the police commissioner said, “They had only come to request us to ensure that the Greek national we have in custody for questioning gets good medical care."

On the insistence of Uttar Pradesh police, Gurgaon police has registered FIRs against all four doctors so far identified in the racket -- Dr Amit Kumar, Dr Upender (who is in police custody), Dr Jeevan Kumar, and Dr Sharaj. They have been charged with criminal conspiracy and under sections of the organ transplant law inviting jail terms of five to ten years and fine of up to Rs 10,000.

A Mumbai police team is said to have set off for Gurgaon to join in the investigations. Said Lal, "This is a big case spanning the whole country and we intend to work in full cooperation with the different state police departments to catch the culprits."

At the Republic Day function, Haryana Chief Minister Bhupinder Singh Hooda was asked if the racket was a reflection on the inept police. He said: "It is the police's fault, the administration's fault, and even the media's fault for not being able to detect such a big scam right under our nose.”