Tokyo police have launched an investigation into a digital exchange that lost cryptocurrency worth more than half a billion dollars to hacking.
Sources close to the investigation told NHK the police on Monday afternoon questioned employees of the exchange operator, Coincheck.
Cryptocurrency NEM worth about 530 million dollars stored in 260,000 customer accounts disappeared after hackers gained unauthorized access to the exchange last Friday.
The sources say employees were interrogated about circumstances that led to the security breach and the company was asked to make its servers available to investigators.
Tokyo police will analyze communications logs on the servers to try to identify the hackers.