Amit Kumar, aged 40 and the subject of an Interpol notice, is believed to have fled to Nepal after the multi-million-dollar scandal was uncovered last month, the paper said.

'We are hoping to arrest him soon,' Upendra Aryal, senior superintendent of police in Kathmandu's Metropolitan Police Crime Division, told the newspaper.

Kathmandu police had found a match of Kumar's passport number and entries in hotels he had checked into.

Last week Interpol issued notices for the arrest of Kumar and his brother, saying the two were the 'subject of national arrest warrants for illegal transplanting of kidneys, cheating and criminal conspiracy'.

'It is believed that during the past eight years around 500 people were forcibly operated on and their kidneys transplanted to foreign patients in a secret operating theatre,' the global police body said.

Six people have been arrested in India over the scandal.

The men behind the illegal operation are believed to have charged up to two million rupees (S$70,929) for a kidney from clients from across the globe, according to local police.

The kidneys are believed to have come from poor migrant workers, some of whom have said they were kidnapped and drugged - although police say the illegal donors were likely to have been paid around 40,000 rupees.

Under Indian law, kidney transplants are allowed only if the organ is donated by a blood relative or spouse, or there is a swap agreement between two needy families. All transplants must also be cleared by the government.

But a huge gap between demand and supply of kidneys because of few body donations has resulted in a flourishing illegal trade. -- AFP