Five men have been arrested from Jamtara and Dumka in Jharkhand for duping people into sharing their ATM card details and one-time passwords for online transfer of money in three cases reported from different parts of Calcutta last year.

One of the accused had posed as a nationalised bank official and siphoned off Rs 2.7 lakh through money wallets, according to a complaint lodged with Parnasree police station.

In the other two cases reported with Watgunge and Bansdroni police, two persons were duped of Rs 1.2 lakh, the police said.

“The modus operandi in all the cases was similar. Someone would call up posing as a nationalised bank official and tell the debit card holder that the card had been blocked and that s/he would have to share the card details and an OTP for re-activating it,” said a senior officer of the anti-bank fraud section of the detective department that made the arrests. “Another common trap was that the person had won a lottery and would have to share his or her card details to get the prize money.”

Those who received the call would either be scared because their card had been blocked or happy that they had won a lottery and, in both cases, share the card details unsuspectingly, the officer said.

Of the five people arrested from Jharkhand, two were beneficiaries of the bank accounts where the money was transferred, one was the owner of a mobile phone recharge store where the gang used to recharge mobile phones and DTH services using misappropriated money through mobile wallets and the remaining two were their associates.

Each of them had a separate role to play. “One would make the call, the other would keep a phone ready and use the stolen data to immediately transfer money. Then there would be some members who would open bank accounts with fictitious identity documents where the money would be transferred,” said an officer.

All five have been charged with sections of cheating, criminal breach of trust, forgery, fraud and criminal conspiracy and remanded in police custody.