AMSTERDAM (Reuters) - Police forces across Europe and the United States arrested 178 people as part of a crackdown on money laundering last week and identified some 23 million euros ($24.46 million) in stolen funds, the European Union judicial agency Eurojust said.

The arrests were the result of an operation targeting the practice of money muling, where illicit funds are disguised by wiring them through the accounts of intermediaries, or mules, who are paid with a cut of the proceeds.

Some 580 money mules were identified and police interviewed 380 suspects during the operation, which was intended to tackle the growing volume of online payment and card fraud across the continent.

The growing scale of card fraud was highlighted at the weekend, when cyber security analysts said criminals had used malicious software to “jackpot” cash machines in more than a dozen European countries - rigging them so they spit out cash .

Money mules are essential to the money laundering strategies of many criminal networks. Since the practice is often disguised as legitimate employment, many are unaware they are involved in a scam for which they can end up facing criminal charges.

“Money muling may on the surface seem to be a small crime, but (it) is orchestrated by organized crime groups,” said Michele Consinsx, president of Eurojust, which helped coordinate the operation alongside European policing agency Europol.

Authorities from Britain, Bulgaria, Croatia, France, Germany, Greece, Hungary, Italy, Latvia, Moldova, the Netherlands, Portugal, Romania, Spain, Ukraine and the United States were involved in last week’s operation.