Police say they have increased patrols around headquarters of nine conservative media outlets in Seoul after North Korea vowed to soon carry out a "special military action" on them by "unprecedented means and methods."
South Korea's government says it is concerned about Pyongyang's threat to reduce to ashes, in several minutes, the support base for the country's president, including several broadcasters and a leading daily newspaper, the Dong-a Ilbo.
Foreign ministry spokesman Cho Byung-je characterizes the latest threat from Pyongyang as “very dangerous and harsh.”
Cho says South Korea's government and military are strengthening their security postures and are on alert to prepare for any situation. He also warns that any military provocation by North Korea will be answered with a punishment by the South.
At the defense ministry, spokesman Kim Min-suk tells reporters he can say little about the possibility of fresh provocations by North Korea.
Kim says South Korean forces are monitoring the North's military but he cannot elaborate.
Officials in the South Korean government say there are no reports of any unusual military movements in the North.
That has led to speculation that the unique assault North Korea's military vows to carry out against the South could be nontraditional, such as cyber attacks on the government and media.
Kim Hung-kwang, who was a computer science professor at a North Korean university - and now heads a defectors' intellectual group - says Pyongyang has a proven capability for distributed denial of service (DDoS) attacks via the Internet.
Kim says he anticipates North Korea will attempt something much more paralyzing than those previous attacks, such as taking down South Korean government internal computer systems. And as far as an attack on the South Korean media, he says, based on Monday's declared threat by Pyongyang, it will be something unexpected and unprecedented.
Tension has been high on the Korean peninsula since the sinking of a South Korean naval ship in the Yellow Sea and the shelling of one of its frontier islands in 2010.
North Korea has denied any involvement in the first incident but acknowledged the second attack, saying it was responding to the South's provocative military exercise in disputed waters.
The North has a long history of terrorist attacks against the South, including attempts to assassinate South Korean presidents.
In recent days Pyongyang's state media reported North Koreans rallied in the streets to demand South Korean president Lee Myung-bak be killed.
North Korea has accused Lee of the “unforgivable sin” of insulting the country while mourning was under way for its late leader, Kim Jong Il and then celebrating, this month, the centennial of the birth of the nation's founder, Kim Il Sung.
