South Korea on cyberattack alert as sites shut

South Korea has issued a cyberattack alert after government websites were shut down Tuesday by hackers claiming to belong to the Anonymous collective.

The sites of South Korea's presidential office, government agencies and a media outlet went down around 9:30 AM on Tuesday — the 63rd anniversary of the start of the Korean War.

Immediately after the hacking attack, the Cheong Wa Dae Web site showed messages in red, including one that referred to the ruler of North Korea as "Great Leader Kim Jong Un."

The message carried a photo of South Korean President Park Geun Hye and read: "We Are Anonymous. We Are Legion. We Do Not Forgive. We Do Not Forget. Expect Us."

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For the next two hours, the websites of at least two major broadcasters, the Saenuri Party's provincial pages and the National Tax Service briefly went down.

Officials told the Associated Press that they were still investigating whether hacking was responsible.

Anonymous said it was not involved in the apparent attack on South Korean servers. If it had been, it would mark a significant departure from the group's previously stated aims: in the past, Anonymous has claimed to have targeted North Korean websites under the code name "#OpNorthKorea." 

Indeed, less than three hours after South Korean sites were disrupted on Tuesday, Anonymous hit North Korean sites with denial of service attacks (DDoS). An Anonymous Twitter account claimed the hacktivists brought down the websites of the state-run Korean Central News Agency (KCNA), a daily newspaper, the Rodong Sinmun, and others.

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Last week, the group announced it would release secret North Korean military documents on Tuesday.

South Korean officials say that North Korea orchestrated a cyberattack in March targeting South Korean broadcasters and banks, and shutting down tens of thousands of computers and servers.

Seoul said that its investigation pointed to North Korea's military-run spy agency as the culprit. The isolated state was accused of similar attacks in 2009 and 2011, although skepticism among the South Korean public remains.

North Korean hackers probably target the South Korean news media to show their contempt for them as capitalist mouthpieces, analysts say.