SEOUL, June 25 (Yonhap) -- Unidentified hackers attacked the websites of South Korea's presidential office, another government agency and some media organizations on Tuesday, claiming they are part of the hacktivist group Anonymous.
The cyber attacks occurred around 9:30 a.m. at the home pages of Cheong Wa Dae and the Office of Government Policy Coordination. Both websites were shut down for repair.
Right after the hacking attack, the Cheong Wa Dae website showed messages in red, including one that read "Great leader Kim Jong-un," the North's top leader.
For 10 minutes from 10 a.m., it was posted along with the message, "We Are Anonymous. We Are Legion. We Do Not Forgive. We Do Not Forget. Expect Us," along with a photo of President Park Geun-hye.
It is unclear if North Korea was involved in the attacks.
Also unclear is whether the Anonymous hacktivist group was behind Tuesday's attacks. The group has said it will launch cyber attacks on dozens of North Korean websites on Tuesday, the anniversary of the outbreak of the 1950-53 Korean war.
The Cheong Wa Dae website is now showing a message that it has been temporarily suspended to check its system. The website of the Office of Government Policy Coordination is also displaying a similar message.
Websites of some media organizations, including the conservative mass daily Chosun Ilbo, and several homepages of the ruling Saenuri Party's local chapters were paralyzed early Tuesday by alleged hacking.
"It is verified that not only Cheong Wa Dae and the Prime Minister's office but also some media outlets were hacked," an official at the National Police Agency's cyber terror response team said. "It seems that a massive cyber attack has started."
Following the cyber attacks, the South Korean military upgraded its information surveillance status and increased the number of cyber security personnel to monitor any attempts to infiltrate into the military network system.
The Joint Chiefs of Staff (JCS) upgraded its the current status of Information Operation Condition (INFOCON) from Level 5 to Level 4. The five-tier threat level system has been used by the military to defend against a computer network attack.
"So far, there was no attempt of hacking into the military network," a JCS official said. "As the military separately operates Internet and Intranet, it is hard to break into the military's internal network system."
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