Japan’s Tokyo Stock Exchange has shut down all trading for a full day due to a system technical error.

The exchange says the glitch is not related to hacking, it has yet to say when trading will resume.

The TSE said it would halt trading for all of Thursday as it works to resolve the system failure, which was detected two hours before markets were set to open. The TSE also added that it sincerely apologizes for any inconvenience caused to investors.

The Japan Exchange Group, a spokesperson for the exchange’s operator, says the error was not caused by a hack but offered few other details declining to provide a restart time.

The glitch is not the TSE’s first technical problem, from time to time encountering other errors over the years, though trading is rarely outright halted.
When the exchange was forced to close markets for more than four hours due to a buggy system upgrade, Thursday’s computer failure marks one of its largest since 2005.

According to local media, the Nagoya Stock Exchange, Fukuoka Stock Exchange, and Sapporo Securities Exchange have also shuttered trading for the day which all use the TSE’s system.

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