By Petlee Peter : After phishing cases, in which credit card details of the victims are obtained by the fraudsters over email, it is vishing, where such information is gathered over phone that has come to light in the city. The Chennai police is probing three vishing cases, in which the victims were cheated of over Rs.1.5 lakh.

The complaints were lodged with the Central Crime Branch in February and March. According to CCB sources, the fraudsters managed to obtain the one-time password (OTP), issued by the bank, from the victims over phone.

The Cyber Crime Cell of the CCB, which has been handling phishing cases for many years, has also been entrusted with the vishing (derived from the combination of voice and phishing) cases.

• Click to Read: What is Vishing ?

The first complaint was lodged by a businessman, who said that he had received a phone call in February from a man who identified himself as an executive of the bank where the victim holds an account. The culprit said he was calling in connection with an account upgradation procedure. He mentioned some details of the victim's bank account, including the recent transactions and purchases made using the credit card. The suspect told the victim that an alpha-numerical code will be sent as an SMS in a few minutes as part of the procedure, an investigating officer said.

Investigations revealed that the code was in fact an OTP, which is sent by the banks to those customers who use their credit card for an online purchase. In this case, the suspect used the businessman's credit card information to purchase some electronic items online and even while doing so he had called the victim.

“The victim received the password on his mobile phone which he thought was an account authentication code and read it out to the suspect when he called a few minutes later,” the CCB officer said.

The victim realised that he had been cheated only after he received an SMS about the use of credit card for the purchase made online.

Two others complainants were also cheated in a similar fashion, according to CCB sources.

Police suspect that ‘insiders' in banks where the victims have accounts might have leaked the credit card details to the fraudsters. A thorough investigation is under way.