In the latest instalment of a saga that saw investors around the world defrauded out of as much as US$16 billion, the co-founder of a disgraced cryptocurrency firm has agreed to testify against the company’s one-time chief, his sister.

Federal prosecutors in Manhattan have brought fraud charges against the co-founder of a cryptocurrency scheme that allegedly defrauded would-be investors of as much as US$16 billion, but experts warn there is still a long way to go before justice is brought to the victims of the scam.