By Kim Eun-jung
SEOUL, March 20 (Yonhap) -- South Korea's military has upgraded its information surveillance status as investigations were under way to figure out potential causes of network crashes at major broadcasters and banks on Wednesday, the defense ministry said.
The latest move comes as servers at television networks YTN, MBC and KBS as well as two major banks Shinhan Bank and Nonghyup were paralyzed. Investigations are currently under way to figure out possible causes of the outages.
Defense minister Kim Kwan-jin convened an emergency security meeting at around 3 p.m. to review the military network system and upgraded its the current status of Information Operation Condition (INFOCON) from Level 4 to Level 3. The five-tier threat level system has been used by the military to defend against a computer network attack.
"Currently, the military network is operating normally," ministry spokesman Kim Min-seok said. "There were no (hacking) attempts from outside."
While initial speculation centered on a potential hacking attack by North Korea, which has hacked South Korean institutions before, Kim said it was not immediately known whether the North was involved in the alleged cyber attack, though he did not exclude the possibility of the communist nation's involvement.
The network outages occurred during a state of elevated military tensions as Pyongyang denounced ongoing joint drills by South Korea and the U.S., which are currently underway, and threatened to cancel the 1953 Armistice Agreement that ended the Korean War.
As there may be further hacking attempts against websites of government organizations, the National Intelligence Service, which oversees state websites, is looking into the server outages with the Computer Emergency Response Team and Cyber Command, Kim said.
"The military will cooperate with other related agencies to figure out the causes of the network paralysis," Kim said.
A string of cyber terrorist acts blamed on Pyongyang in the past few years has raised concerns that Seoul needs to be prepared for future attacks.
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