Authorities in the US are considering a $250,000 bounty on spammers in an attempt to close them down.
The US Federal Trade Commission (FTC) has suggested rewards of anything from $100,000 to $250,000 for information.
The organisation believes that people most likely to identify a spammer and provide evidence would be "whistleblowers" or insiders. It suggested that amateur cyber-sleuths would be unlikely to track down spammers.
But the FTC admitted that, even with high-dollar rewards, whistleblowers may be reluctant to come forward because they could end up facing legal liability themselves.
Graham Cluley, senior technology consultant at security company Sophos, said that, although a few US spammers have been convicted, these have done little to stem the tidal wave of unsolicited email.
"It is therefore unsurprising that the FTC is proposing a bounty for the heads of spammers," he said in a statement.
"If this is what is necessary to make the spammers sleep uneasily in their beds at night, it is probably the right step."
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