Your email spam filter works overtime to keep sketchy investing opportunities and cheap Viagra offers out of your inbox, but you've probably seen some scams sneak through. That's because email fraud operations are a multibillion-dollar business, often run by Nigerian-based syndicates[1] that have members—not to mention targets—around the world. And on Monday, US officials announced a massive international initiative, Operation Wire Wire, that resulted in the arrest of 74 alleged email fraudsters.

The move is significant given that email scamming has gone mostly unchecked for years, but Operation Wire Wire still represents a small drop in a massive ocean of fraud. And while it particularly targets some of the money mules who underpin criminal payouts, the overall infrastructure behind these spamming campaigns is massive and inveterate. It would take major disruption to see a noticeable improvement.

Nigerian email rackets predictably target individuals, especially vulnerable populations like the elderly, but they also increasingly generate cash from a type of fraud called business email compromise, which fleeces companies of all sizes. BEC scams focus on employees with financial authority, and position fraudsters as company executives or third-party vendors that a business works with or could conceivably contract with. Employees complete a bill or invoice payment like normal, but the money really goes to scammers.

The Department of Justice—working with the Department of Homeland Security, Department of the Treasury, and Postal Inspection Service—arrested 42 people in the US, 29 in Nigeria, and three in Canada, Mauritius, and Poland who are allegedly connected to spamming operations and particularly money muling.

“Fraudsters can rob people of their life's savings in a matter of minutes,” Attorney General Jeff Sessions said in a statement. “The Department of Justice has taken aggressive action against fraudsters in recent months...[and] we will continue to go on

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