Dr Kumar, against whom an Interpol has served a Red Corner notice, gained command over these two languages, besides English, during his several visits abroad, said Uttar Pradesh Additional Director General of Police Brij Lal.

The police have so far not come across any website through which Dr Kumar lured foreign clients. The computer seized from his laboratory contains health details of just four patients, two of which hailed from Greece. The police suspect that Kumar’s first wife Poonam — based in Canada — and a Greek female friend helped him lure clients.

Besides, word of mouth publicity from previous clients also helped him in getting new patients.

“It has not come to light how he contacted clients but he had been in the kidney transplant business for the last 15 years. It is highly possible that he had good contacts in dialysis centres abroad,” said a senior police officer.

Police officials said the clients were picked up from the Indira Gandhi International Airport in New Delhi and were transported to a luxurious guesthouse in Gurgaon.