An unprecedented international police campaign across Europe and the U.S. has led to 110 arrests of "boiler room masterminds" believed to be responsible for millions of dollars of investment fraud.
The City of London Police and Spain's Policía Nacional launched the investigation in 2012 after a number of reports emerged of investors worldwide being sold bogus shares in carbon credits, gold, renewable energy, forestry, eco projects, wine and land.
The U.K's National Crime Agency along with other anti-crime organizations such as the U.S. Secret Service and Homeland Security Investigations helped to execute and plan the operation that has been years in the making.
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Expensive sports cars, including an Aston Martin, Ferrari and a Mustang, along with designer clothes, watches and large amounts of cash were seized from several different private addresses and buildings after 35 search warrants were approved.
The suspects are believed to be part of a highly organized network of criminals that run 'boiler rooms' in Europe – where fraudsters sell questionable investments, such as worthless penny stocks or non-existent shares, by phone.
The rooms are mainly located in Spain and often run by teams of young men cold-calling investors. They promise high returns but those who invest, often the elderly and vulnerable, usually end up losing their money.
City of London Police Commander, and National Economic Crime Co-ordinator, Steve Head, said: "This is a landmark both from an investigative perspective and in terms of our close working partnership with other law enforcement agencies, most notably the Policía Nacional.
"It is our most important investigation ever, targeting people we believe are at the top of an organized crime network that has been facilitating boiler rooms across Europe and which is suspected of being responsible for millions of pounds of investment fraud," he said.
Arrests were made across four countries after the suspects were found to be tricking innocent people into backing investment scams, "that wreak financial and emotional destruction."
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Of the 110 arrests, there were 84 in Spain, 20 in the U.K., two in the United States and four in Serbia with the majority of people arrested on suspicion of money laundering and fraud offenses.
The operation also led to the closure of what are believed to be 14 boiler rooms in Spain, two in the U.K. and one in Serbia.
One victim lost all of his life savings as a result of the fraud, while another lost a six figure sum that she invested in order to try and create a secure financial future for her daughter.
—By CNBC's Jenny Cosgrave: Follow her on Twitter @jenny_cosgrave