The former head of the legal and compliance department of the fraudulent cryptocurrency OneCoin, Irina Dilkinska, has received a four-year prison sentence, the U.S. Attorney's Office has announced.

The 42-year-old Bulgarian woman had previously admitted helping to launder hundreds of millions of US dollars in proceeds from the OneCoin scam. As a result, she pleaded guilty in November.

OneCoin was a Ponzi scam based in Bulgaria that was run between 2014 and 2018. The fraudsters promised huge profits, guaranteed returns and marketed their crypto project as a "Bitcoin killer."

U.S. District Judge Edgardo Ramos rejected Dilkinska's request to avoid jail time and return to Bulgaria to care for her two young children, Bloomberg reported.

She is not the only former OneCoin executive serving time in prison for fraudulent activities. Co-founder Greenwood was also sentenced in September to 20 years in prison for fraud and money laundering.

The judge called her "a woman of great intelligence who should have known better" and also ordered Dilkinska to pay $118.4 million in compensation for her involvement in the OneCoin scam.

Cryptoqueen Ruja Ignatova is still missing as the alleged mastermind behind OneCoin. As such, she is on the FBI's "Ten Most Wanted" list and was convicted in absentia for securities fraud and money laundering, among other charges.

Some are already speculating that she was murdered. Her brother, on the other hand, is free again after serving three years for his involvement in the infamous US$4.4 billion fraud.