SEOUL, March 20 (Yonhap) -- Computer networks at major South Korean banks broke down simultaneously on Wednesday, prompting the financial watchdog to launch an investigation to determine the cause and raise its crisis alert level by one notch.
According to bank officials and the Financial Supervisory Service (FSS), Shinhan Bank, the flagship unit of the country's No. 3 banking group Shinhan Financial Group Co., experienced interruption in its electronic transaction system around 2 p.m., including Internet banking, smartphone banking and use of automated teller machines.
Shinhan Bank said the lenders' electronic transaction system was restored about two hours later.
Two insurance arms of NongHyup Financial Group Inc. also reported computer network shutdowns at some of their branches at 2:15 p.m., with some of their employees finding files on their hard drives had been erased. NongHyup Financial Group also said its computer network was normalized two hours later.
Computer glitches were also reported at Woori Bank and Jeju Bank, a subsidiary of Shinhan Financial Group Co.
The financial regulator said it has yet to determine what caused the system failures.
The financial authorities raised its crisis warning level to "caution" from "attention" soon after the initial report on network failures.
"While three banks were damaged from the attack, we will check whether hackers targeted other local banks as well," an official from the FSS said. "We will look into the three banks' security systems to find out the flaws."
"We suspect that there was something wrong with the database for Shinhan Bank," said Song Hyun, chief of the regulator's information technology supervision bureau.
The network failure caused inconveniences for bank users trying to make transactions.
The affected lenders decided to extend their operating hours till 6 p.m. to make up for inconveniences and disturbances caused by the system failure. Banks in South Korea usually close at 4 p.m.
The FSS said no network or financial damages have been reported from brokerage houses, or other commercial banks as of yet. Nonetheless, other financial firms began to prepare for any emergency incidents.
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