The Tokyo Stock Exchange returned to normal on Friday after trading in all shares was halted for the whole session the previous day due to the worst-ever glitch since the bourse's trading system was fully computerized in 1999.

The 225-issue Nikkei Stock Average temporarily rose more than 180 points Friday morning, before turning negative in midafternoon trading after U.S. President Donald Trump said in a Twitter post that he tested positive for the novel coronavirus.

"We apologize anew for the significant trouble we caused due to the system glitch," the bourse's operator Japan Exchange Group Inc. said in a statement released ahead of the start of the day's trading at 9 a.m.

Finance Minister Taro Aso, who is also in charge of financial services, told a press conference it was "extremely deplorable."

Later in the day, the Financial Services Agency, the country's financial watchdog, ordered both the TSE and its operator to report on the cause of the glitch, according to government sources.

Securities firms were busy responding to their customers as all orders they had received before the suspension of trading on Thursday were canceled and investors had to place new orders.

Investors across the country, meanwhile, expressed relief at the restart of trading at the Tokyo bourse.

In front of JR Tokyo Station, a 52-year-old shareholder in restaurant industry issues from Chiba Prefecture said while watching an electronic stock price board at around 9 a.m., "I'm glad that stock prices didn't fluctuate because I was anxious about how they would perform after trading was halted all day" the day before.

In the southwestern Japan city of Fukuoka, Akira Kamei, 66, said he felt uneasy that he could not see share-price comparisons from the previous day on the stock board he was watching because of Thursday's trading suspension.

"Still, I am relieved because normal everyday life has returned," said Kamei, who has been trading shares for more than 30 years.

A 65-year-old university staff member in Kyoto who owns auto stocks said, "We'll be in trouble if overseas players lose confidence (in the Tokyo bourse). I want (JPX) to fully prepare a back-up system so as not to repeat a similar incident."

JPX said Thursday the technical trouble stemmed from a defect in hardware in the bourse's trading system and that the automatic backup system also failed.

The faulty hardware was replaced and handed over to Fujitsu Ltd., its developer, for further investigation, the TSE said.

The market capitalization of the TSE, with about 3,700 listed companies, is the third largest in the world, behind the New York Stock Exchange and Nasdaq in the United States.

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