Police in South Africa are looking into criminal cases brought by investors claiming to have been defrauded by Africrypt, a crypto platform run by two brothers who have since disappeared, Bloomberg reported Tuesday.

The investors are seeking the arrest of the brothers, Ameer and Raees Cajee, after being offered some of the lost investment by Pennython Project Management, a mystery investor in Dubai, according to Bloomberg.

The Hawks, the arm of the South African police that tackles organized crime, corruption and other serious crime, is investigating in four provinces and cities including Johannesburg and Durban.

The Cajees disappeared in April after telling investors the platform had been hacked, with bitcoin worth around $3.6 billion allegedly going missing. In June, the brothers’ attorney at the time, John Oosthuizen, said they denied the allegations of wrongdoing, and that the money was missing because of a hack. Just two days later, Oosthuizen said his firm’s relationship with the brothers had been terminated.

The Africrypt incident was one of two major scams that have taken place in South Africa in the last 18 months. The other involved Mirror Trading International, which defrauded investors of $589 million in August 2020.

As a result, South Africa’s Financial Sector Conduct Authority decided to prepare a regulatory framework on how crypto trading should be conducted. The framework is set to be unveiled early this year.

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