A woman known as the “Crypto Queen” has been added to the FBI’s top 10 most wanted list.
Ruja Ignatova allegedly defrauded victims out of $4bn in a cryptocurrency scam in what a US prosecutor described as "one of the largest Ponzi schemes in history".
She disappeared in 2017 after discovering that her boyfriend was cooperating with an FBI probe into her company OneCoin.
Ms Ignatova, a German citizen, was last seen boarding a flight from Bulgaria to Greece.
OneCoin started to offer buyers commission if they sold the self-described cryptocurrency to other people in 2014.
But according to the FBI, OneCoin was worthless and not protected by the blockchain technology used by other cryptocurrencies. Her story was the subject of a BBC podcast called 'The Missing Cryptoqueen' in 2019 that tried to track her down.
Federal prosecutors claim that it was a Ponzi scheme disguised as a cryptocurrency.
"She timed her scheme perfectly, capitalising on the frenzied speculation of the early days of cryptocurrency," said Damian Williams, Manhattan's top federal prosecutor.
The 42-year-old was charged with eight counts including wire fraud and securities fraud in 2019 for running the Bulgaria-based company.
Investigators have had difficulty tracking Ms Ignatova because she was able to escape with at least $500m to help her go into hiding.
"Money can buy a lot of friends, and I would imagine she's taking advantage of that,” Michael Driscoll, the FBI's assistant director-in-charge in New York, said.
It is likely that she has changed her appearance and has high-quality forged documents, experts claim.
A $100,000 reward is on offer for any information leading to her arrest.
She is the only woman on the top 10 list. The FBI adds to it when they believe the public could help in tracking them down.