THANE: Police have busted a fake call centre in Navi Mumbai, from where cyber frauds involving at least Rs 12 crore were allegedly committed mostly against US citizens, and arrested 20 persons in this connection, officials said on Thursday.

The police suspect that the scale of the crime is "very large" and many wanted accused are involved in it.

The action against this call centre, which was in operation in Turbhe area of Navi Mumbai was taken on Thursday, they said.

Navi Mumbai Cyber police station and the Crime Branch took the action.

The police received a tip-off on November 18 that a call centre was in operation under the guise of various bogus companies to defraud citizens.

Immediately, a joint team of police conducted a raid and uncovered two distinct methods of fraud being run from there.

In the first method, the employees of the call centre targeted US-based citizens through WhatsApp groups and lured them by promising high returns on stock market investments.

Separately, they also targeted the American citizens by carrying out ransomware or malware attacks on their computers, an official statement said.

The raid brought to light a "massive scale of the financial crime", it said.

The investigators found 97 persons working at the fake call centre.

They also found several WhatsApp numbers and bank accounts being used by those found at the location, it added.

"The transactions of 71 bank accounts, details of which were sent to US citizens and others, for fraud were checked.

Out of these, 61 accounts were found to have transactions worth a total of Rs 12.29 crore.

Some of these bank accounts were checked on the National Cyber Crime Reporting Portal (NCCRP) developed by the Union Ministry of Home Affairs (MHA).

It was found that 31 cyber fraud complaints have been registered across the country," the statement added.