The case, which is being investigated by the FBI and the US Department of Homeland Security, has charged Mr Patel as well as over 80 other individuals and five India-based call centres for their roles in the fraud, which primarily is a money laundering scheme.
Mr Patel pleaded guilty before US District Court Judge David Hittner of the Southern District of Texas. His sentencing is scheduled for August 7. Mr Patel admitted that he and his fellow conspirators perpetrated a complex scheme in which individuals from call centres located in Ahmedabad impersonated officials from the Internal Revenue Service or US Citizenship and Immigration Services in a ruse designed to cheat people located across the United States, the Department of Justice said in a statement.
Using information obtained from data brokers and other sources, the call centre operators targeted people in the US, who were threatened with arrest, imprisonment, fines or deportation if they did not pay money allegedly owed to the government. They were told that the police would be at their doorstep soon to raid their homes if they do not pay. Many unsuspecting Americans agreed to pay anywhere between 500 and 60,000 dollars, investigators said.
The victims who agreed to pay the scammers were then instructed how to make the payment, including by purchasing stored value cards or wiring the money. Once the payment was made, the call centres would immediately turn to a network of "runners" based in the United States to liquidate and launder the fraudulently-obtained money.
Mr Patel said that he worked as a "runner" since January 2015, operating primarily in New Jersey, California and Illinois. He is the third Indian national to have pleaded guilty in what is called 'the call centre scam'.
Two others in the US, who have pleaded guilty in the call centre scam are 43-year-old Bharat Kumar Patel, and 28-year-old Ashvinbhai Chaudhari. More than twenty people have been arrested in the US so far.
Last month, the mastermind of the call centre scam - Sagar Thakkar, who also goes by the name 'Shaggy', was arrested. According to the US Department of Homeland Security, Thakkar is said to have extorted nearly $300 million from the scam, which has been operational since 2013.
Since October 2016, police have raided call centres in Ahmedabad and Thane. Similar call centres in Gurgaon and Noida could also come under the scanner as the case proceeds, the police said. These call centres scammed nearly 6,500 Americans and estimates suggest collected hundreds of millions of dollars.
The mastermind - Sagar Thakkar - who is now in police custody, had even gifted an Audi car worth Rs. 2.5 crore to his girlfriend. He was often accompanied by a battery of bouncers and bodyguards and was fond of high-end vehicles. Investigators added that he had purchased an Audi R8 car, valued at Rs. 2.5 crore, from cricketer Virat Kohli in May last year. However, Thane police chief Param Bir Singh said that Mr Kohli was an "innocent seller" who had no idea who he was dealing with. The luxury car was seized from Ahmedabad.
Since October last year, investigators have arrested more than 20 people in the United States, while nearly 80 people have arrested in India.
(With inputs from PTI)