TEMPO.CO, Jakarta - South Korea's computerised nuclear power plant operation system has been hacked, but the incident does not pose a threat to the safe operation of South Korea's 23 nuclear power plants, according to a statement released by Seoul on Monday.

The hacking came to light right after the United States (US) accused North Korea of hacking into the database of major film production company, Sony Pictures. It is known that South Korea is technically still at war with its reclusive Northern neighbour.

Meanwhile, South Korea's Ministry of Energy claims that it remains confident that its nuclear power plants are sufficiently equipped to withstand cyber attacks, which potentially harms the safe operation of the reactor.

"We believe that our nuclear power plants have been sufficiently designed in such a way that no security risk would arise from cyber attacks," said the Deputy Minister of Energy, Chung Yang-ho, to Reuters.

On the other hand, Korea's Hydro and Nuclear Power (KHNP) - the operator of South Korea's nuclear power plants, which is a subsidiary of Korea Electric Power Corporation - has said that the hackers come from a group of people who wishes to stir up social unrest among South Koreans.

"It is highly improbable that a hacker could single-handedly stop the operation of our nuclear power plants, because our units are fully independent and closed," said an unnamed KHNP official to Reuters.

Both Chung nor the KHNP official stopped short of placing the blame on North Korea during their interviews with Reuters. Both also declined to comment on a Twitter message who is claimed to have been sent by the hacker, who demanded that three reactors must be shut down before Thursday.

The owner of the Twitter account claims to be the head of an anti-nuclear organisation based in Hawaii. The owner threatens to upload stolen, classified documents belonging to the nuclear company if its demand went unheeded.

Authorities in Seoul has launched an investigation into the hacking and the theft of classified documents, which includes information on South Korea's nuclear reactors - including the all-important blue print and other sensitive information.

Authorities have managed to track the IP address of a blog who uploaded the stolen documents, although the blog's owners have denied involvement in the hacking, and claimed that the blog was hacked by unknown persons.

ANTARA NEWS