Six people have been arrested in a joint operation by Delhi Police, US' FBI and Interpol

Several citizens of the US and Uganda were duped of a total of 20 million dollars through call centres being run from India, Delhi Police have said.

Six people, four in India and one each in Uganda and Canada, have been arrested in a joint operation by Delhi Police, the US' Federal Bureau of Investigation and Interpol.

The four arrested from Gujarat and Uttarakhand have been identified as Vatsal Mehta, Parth Armakar, Deepak Arora and Prashant Kumar. According to police, Mehta was the mastermind of the racket and Armakar ran call centres in Uganda and India.

On how the gang operated, police said the callers would dial people in the US and pose as officers from the country's anti-drugs agency Drug Enforcement Administration.

In some cases, police said, the callers would tell the targets that their name had come up in a case of child pornography after some objectionable materials were found during a check on US-Mexico border. The callers would ask them to pay a hefty fine and warn them of serious consequences if they didn't pay.