When 65-year-old Madam Lee picked up a call on her landline last Wednesday, she thought it was a Singtel customer service employee contacting her about problems with her broadband connection.
The caller said he would rectify any problems with her Wi-Fi connection if she followed his instructions, and Madam Lee believed him.
It resulted in her staying on the line for over two hours, following the man's detailed instructions on what to do on her computer.
This included her having to give the man - who she said did not sound Singaporean - remote access to the computer.
Over the two hours, the caller also had Madam Lee log in to her Internet banking account and give him some very personal information, including a one-time password and her latest transactions.
The caller even told her that he would connect her to the "cyber police". She was then connected to another person - who told her that her IP address was being used in various countries.
Little did she know that these were scam callers, who later made off with over $300,000 from three different bank accounts. No part of this sum was recovered.
"Throughout this process, they kept telling me not to talk to anybody, not to inform anybody, and to keep the landline on and my handphone switched off. Not knowing anything, I just followed through. That's when it all happened," Madam Lee said.
The scammers went so far as to tell Madam Lee that her Singtel IP address was being used by people from other countries. They convinced her by sending her a world map and a message from "Interpol" with a picture attached of a Russian man who was supposedly using her account.
"They even told me to write down some codes and that the cyber police would come to my home and I should pass the codes to them," she said.
After she hung up, she tried to call the official Singtel customer service number on another line, but could not get through.
Feeling uneasy, she called her bank, and found out that various transfers were made from her account to a local account and foreign accounts as well. It turned out that the scammers had also raised the withdrawal limit on her accounts in order to make a big transfer at once.
"It was very traumatising because it didn't only affect me. It affected my family members who had joint accounts with me too," she said.
The Singapore Police Force warned that there have been a significant number of such scams reported recently.
From January to October, at least 156 reports of such scams were lodged, with victims losing at least $6 million in all. Last month alone, at least 50 victims fell prey to scams similar to Madam Lee's case, in which the scammers impersonate personnel from local telecommunication service providers such as Singtel and StarHub, or even police officers, to gain remote access to the victims' computers.
In most cases, the scammers would deceive victims into thinking that there were issues with their Internet connections, and persuade them to download remote access software applications like TeamViewer or AnyDesk.
In some cases, the scammers even claimed to be from the "Cyber Crime Department of Singapore" or the "Cyber Police of Singapore" to make victims think they had committed a crime.
The police advise members of the public who have fallen prey to such scams to immediately turn off their computers, report the incident to their bank to halt further activities on their accounts and make a police report. One-time passwords for banking transactions should never be given to other parties.