Workers of a call centre in Thane defrauded Americans by pretending to be from the IRS.

Highlights FBI officer meets Thane police, tax and homeland security to also visit

Probe unique, has made big dent in global racket: Officer reportedly said

Call centre workers had defrauded Americans by pretending to be from IRS

US agency FBI has begun assisting the police in investigating a call centre scam near Mumbai that defrauded more than 6,000 Americans of millions of dollars."Suhel Daud, an FBI or Federal Bureau of Investigation officer of Indian origin and a cybercrime expert, today met Param Bir Singh, police chief of Thane, a Mumbai suburb where the call centres are located, to gather and share evidence on the con.The FBI officer reportedly told the Thane police that their investigation was "one of a kind" and has made a "big dent into the global racket". Mr Daud is one of two FBI officers assigned in India. The legal attache at the American embassy belongs to Bareilly.The Thane Police say they are also expecting teams from the Internal Revenue Service or IRS and the Department of Homeland Security in the US to reach out to them for evidence sharing and cooperation.More than 2,000 people worked at the nine Thane call centres that duped Americans by pretending to be IRS officials and threatening them with tax investigations if they did not pay up, the police said.The alleged mastermind is a 24-year-old called Sagar Thakkar, who, the police fear, may have fled the country. Thakkar along with his sister Reema are absconding. Money extorted by them may have been used to fund their lavish lifestyles as they bought cars and suspected to have made real estate investments.The scam was simple. Call centre workers called Americans and said cops 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, the police said.These call centres scammed nearly 6,500 Americans and estimates suggest collected millions of dollars.Last week, the police swooped in to cut the lines. Nearly 800 workers were questioned and 72 of them were finally arrested.

The police have raided call centres in Ahmedabad and recovered hardware. Through cooperation with the FBI, the Thane police hopes it will be able to establish the money trail from the US to accounts in India.Similar call centres in Noida and Gurgaon could also come under the scanner as the police proceeds with its crackdown.