Police in Singapore have warned men to be more careful about whom they talk to over webcams, reporting an alarming increase in the number of men who've been lured into nude conversations with "foreign" women, only to be blackmailed with video-chat recordings.

In terms of sheer numbers, the increase isn't much — from 11 in 2011 to more than 50 last year — but it suggests a burgeoning scam that could ensnare many more men in the future, the national police force said in a bulletin that was first reported by Singapore's Straits Times newspaper.

Police singled out Facebook and Tagged as especially popular vehicles for the extortion scheme, in which "female foreign suspects ... would 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."

"Unknown to the victims, the suspects had recorded the acts," police said. "These suspects would then threaten to circulate compromising photographs and videos of the victims to extort money from them."

The spike in cases was first noted halfway through last year, leading CrimeWatch, a joint program of the national police and the National Crime Prevention Council, to "re-create" the scam in a (safe for work but entertainingly cheesy) video in June:

Graham Cluley, a consultant with the Internet security firm Sophos,  reported the bulletin Monday on the company's appropriately named Naked Security blog and warned of another potential hazard:

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

Police offered these tips to keep your money in your wallet:

• Be wary of messages from unknown people who want to befriend you.
• Do not accede to any request that may put you in vulnerable positions, such as performing compromising acts in front of a webcam or giving personal details about yourself when interacting with other Internet users.
• If anyone attempts to extort money from you or should you become a victim of such an attempt, call the police immediately.
• Do not remit or transfer money.

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