TOKYO, Japan (Update 1, 12:12 p.m.) — Trading in Tokyo's stock markets, which are among the world's biggest, was halted for the whole day Thursday after the system was hit by one of its worst ever glitches.
A technical problem involving the delivery of market information was flagged to the operator of the Tokyo Stock Exchange operator and business was stopped less than half an hour before the opening bell.
The decision not to open for the rest of the day was taken around noon, with Japan Exchange Group giving no further details on the cause.
"TSE has decided to halt all listed stocks for all of today. When trade will resume has not yet been decided," it said in a statement, which added that a decision on whether to resume Friday will be announced later.
The glitch hit the country's top Nikkei 225 and Topix indexes as well as exchanges in Nagoya, Sapporo and Fukuoka that operate through Tokyo's system. The Osaka exchange was functioning normally, though, the operator said.
The trading halt closed one of the few major markets that was due to be open in Asia on Thursday, with bourses in Hong Kong, Shanghai, South Korea and Taipei all closed for holidays.
It is the first significant glitch to hit Tokyo since 2018, when a trading system problem left some securities firms unable to execute orders but that only had what was described as a limited effect on overall market activity for the day.
The last time all stock trading was suspended because of a system glitch was on November 1, 2005, when the entire morning session was suspended.
The news raised concerns of a possible cyber attack after the New Zealand Exchange was hit in August, forcing trading halts over several days, though officials said there was no indication so far of foul play in Japan.
"We don't have any information to hand that suggests that," TSE spokesman Hiroyuki Takahashi told AFP. "Right now our focus is to resume trading. We will investigate the cause of this after we achieve that."
Government spokesman Katsunobu Kato said the Financial Services Agency had instructed Japan Exchanges Group to quickly restore operations and investigate the problem.
He said the government also had no immediate suggestion that a cyberattack was involved but added he would "decline to say anything definite" at this stage.
Analysts said the glitch was not likely to have a significant immediate impact on the market.
Nikkei futures contracts were up 0.51 percent shortly before midday, noted Makoto Sengoku, a market analyst at the Tokai Tokyo Research Institute.
"If you watch the futures, they are up. For now, expectations are that the impact will be limited," he told AFP. "The last time something like this happened was in 2005. At that time, the impact was not that profound, I think."