A Swedish national was sentenced to 15 years in prison Thursday after pleading guilty to defrauding thousands of people in a multimillion-dollar Ponzi scheme, the Justice Department announced.

Roger Nils-Jonas Karlsson, 47, pleaded guilty to various securities fraud, wire fraud, and money laundering charges on March 4 for his role in the scheme, which solicited victims to purchase shares in a faux investment venture he named “Eastern Metal Securities,” according to court documents.