Fraudsters have long posed as bank officials or power supply personnel to clean out victims’ bank accounts. Now, they are pretending to be customs officers to execute their plots.

Multiple cases have been reported with the city police where callers introduced themselves as officers of the customs department and claimed that a consignment of narcotics booked in the name of the person receiving the call had been caught and that the matter would be reported to police unless the person paid a hefty amount.

Many people, fearing arrest, litigation or plain harassment, have paid, without verifying the statements, police said.

“One thing is common in all these complaints,” said an officer at Lalbazar.

“First, the fraudster would pretend to be an officer of the customs department and inform the person receiving the call that his PAN and passport details have been found with a consignment of banned psychotropic substances. Then the caller would threaten the person that a police complaint would be lodged against him if he did not pay up. If the person refused to pay, someone posing as an officer of Mumbai police would call him and threaten to arrest him,” the officer at Lalbazar said.

Most of the victims of such fraud are elderly people, the officer said. “The modus operandi was to make it sound authentic. So the fraudsters first call as customs officers and then as police officers.”

To convince the person being targeted that an illegal consignment booked in his name has indeed being seized, the caller asks him to press 9 on the phone to speak to a representative of the courier firm that “transported” the item.

“One the person presses 9, the caller changes his voice and carry on with the chicanery or hands the phone to someone else to do the job,” the officer said.

The police said they have also come across some cases where the persons approached by the fraudsters caught the lie by asking them about the PAN or passport details, which the callers had claimed were in their possession.

“Asking them to verify your PAN or passport number is the easiest way to check the authenticity of the claims. Faced with such questions, scamsters disconnect the call,” said an officer in the cybercrime cell of Calcutta police.

Earlier, too, fraudsters had cheated Calcuttans citing customs department rules. Fraudsters would befriend targets on Facebook and then persuade them to pay money saying gifts sent to them had been detained by the customs department.

“People now have become more cautious and do not fall into such traps laid by virtual friends. So the fraudsters, too, have modified their way of operation and are posing as customs officers,” said the officer of the cybercrime cell.