South African police have arrested six West Africans, allegedly members of a 419 email fraud gang which is thought to have tried to con thousands of pounds out of their victims, according to this report.

Sometime in 1992/1993, I received my first airmail letter with a Nigerian stamp offering me a few million dollars, if only I would let the writer use my bank account to spirit money stolen from the government out of that huge, heroically corrupt country.

You'd think no-one would fall for the scam - known as a 419, after the relevant section of Nigeria's criminal code. But you'd be wrong: a few years ago, the Nigerian government placed ads in the FT, warning people not to be greedy and not to be suckers. If you got trapped, it was your own fault, so don't go running to the Nigerian government for your money back.

The scam, I thought, involved raiding my bank account.. Turns out it's a little more complicated - get your greedy victim to reply, and get the victim to travel abroad to another country, where he's vulnerable, and where the police don't care. And then get the victim to cough up money to facilitate the transaction. This is known as advance fee fraud, a common enough scam. But the Nigerians do it better than anyone else.

A variation on this theme is to hold aforesaid victim hostage until large sums of money are handed over. last year, a Nigerian gang lured a British businessman to South Africa and then held him for ransom. He escaped only because he was allowed to make a phone call and was able to alert his wife by speaking in his native Polish language.

The web site Crimes of Persuasion has several more examples of People held to ransom (scroll down a bit).

Over four or five years, I saw maybe eight 419 letters. These days I'm getting maybe two or three a week by email, both on my own account and from readers, purporting to come from Zimbabwe and Sierra Leone as well as from Nigeria.

The Nigerian government is trying to combat 419: you can do your bit by ignoring these ludicrous letters. ®