Mizuho Bank suffered its fourth system glitch in two weeks Friday, dealing a serious blow to the management of one of Japan's top banks that has a history of troubling customers with technical problems.

The latest glitch affected foreign currency-denominated remittances for corporate customers in the country. Around 300 transactions were delayed for about four to five hours due to hardware trouble that occurred at 11:40 p.m. on Thursday at its data center, the unit of Mizuho Financial Group Inc. said.

The glitch has also affected overseas remittances, but details are still being investigated, the bank said, adding both issues were resolved by 7:45 p.m. Friday.

"We take it very seriously that troubles have occurred in quick succession and sincerely apologize," Mizuho Bank President Koji Fujiwara said at an urgently arranged press conference.

On Feb. 28, Mizuho suffered a glitch that affected over 4,300 automated teller machines nationwide, while 5,244 bank cards and books were stuck inside the devices and not returned to their owners. Its systems were overwhelmed when updating the status of fixed deposit accounts and processing other transactions.

All of its ATMs were back up and running by the next day.

The incident was followed by minor trouble on March 3 and last Sunday, sparking criticism from its customers and the country's financial authorities while pressure grew on Fujiwara to take responsibility by stepping down.

The Financial Services Agency has ordered Mizuho Bank to report the details of the incidents.

Friday's trouble, Fujiwara said, has no relations with earlier glitches.

The megabank started running its current system in July 2019 after spending about 400 billion yen ($3.7 billion) to develop it following large-scale system glitches in April 2002 and March 2011.

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