Women are seducing men into webcam cybersex, then blackmailing them.
According to a report in London's Daily Mail, police in Singapore are warning of rise in online scam artists who use attractive women to befriend men on social media sites such as Facebook.
The girls charm the men into undress and performing sex acts, then threaten to post images or videos of them online if they do not pay up.
According to the police, more than 50 such cases were reported in 2012, up from 11 the previous year.
The Daily Mail claims the women start a webcam conversation with the victims and initiate cybersex by undressing themselves first before persuading the male victims to appear nude or perform sexual acts in front of the camera.
Unknown to the victims, the suspects record the acts, then blackmail the men for significant amounts of money. One victim was asked for $50,000.
Web security expert Graham Cluley said cyber scams often went further than just blackmail.
"You can imagine how a man, believing he is being seduced online by a sexy woman, might be all too eager to click on a link she suggests or run a malicious program on his computer," he said. "Before he knows it, his computer could be under the control of a hacker."