Police in Singapore have warned of a rise in online scam artists who use attractive women to ‘friend’ victims on social sites, then seduce them into cybersex on webcams to blackmail them.

The women, who prowl for men on sites such as Facebook, charm the men into undressing or 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.

Singapore Police said the women commence 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 webcams.’

It added in a post on its website: ‘Unknown to the victims, the suspects had recorded the acts.’

Now Singapore TV station HD 5 has created a 10-minute ‘reconstruction’ of the scam.

It shows a young, bookish student called Danny accepting a friend request on Facebook from an attractive stranger called Lily.

After a few days chatting online, Lily – who is now his ‘girlfriend’ – manages to convince Danny to undress on camera before abruptly disappearing.

Danny is then contacted by e-mail and phone call from a man who is demanding $50,000.

Graham Cluley, of Web security firm Sophos, wrote on his blog that if such a scam was to spread, it could encompass more than just blackmail, CNN reports.

He said: ‘You can imagine how a man, believing he is being seduced online by a sexy woman, might be all too eager to click a link she suggests or run a malicious program on his computer.

‘Before he knows it, his computer could be under the control of a hacker.’

Singapore Police have said people should be wary of strangers befriending them on social networks and to avoid giving away personal details or ‘performing compromising acts.’

They also urged users to call authorities immediately if someone tries to extort money from you.

Cluley’s advice is somewhat simpler: ‘Keep your trousers on chaps’.

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