North Korea has threatened to shut down Kaesong Industrial Complex it jointly operates with South Korea that stands as the last significant symbol of cooperation, after reiterating that it considered the Korean Peninsula back in “a state of war”.

The eight-year-old Kaesong complex in the North Korean border town of the same name, is a crucial source of badly needed cash for the heavily sanctioned North.

The industrial park funnels more than $92 million a year in wages for 53,400 North Koreans employed there, and its operation has survived despite years of military tensions. The latest threat to close down Kaesong came amid a torrent of bellicose statements by North Korea in recent days, widely seen as a strategy to increase pressure on South Korea and the US to soften their policies on the North.

Although South Korean officials reasserted that they were ready to retaliate if North Korea committed any military provocations, they said they saw no imminent sign of any such attacks.

On Saturday, cross-border traffic operated as normal, allowing hundreds of South Koreans to travel to and from Kaesong.

Over 300 South Koreans remained in the complex, where 123 South Korean textile and other labor-intensive factories employ the North Korean workers, at an average monthly wage of $144.

The fate of Kaesong is seen as a crucial test of how far North Korea is willing to take its recent threats against the South. Its continued operation was often seen as a sign that Pyongyang’s verbal militancy was not necessarily matched by its actions.

“The South Korean puppet forces are left with no face to make complaint even though we ban the South side’s personnel’s entry into the zone and close it,” North Korea said Saturday in a statement carried by its official KCNA.

North Korea said its dignity was insulted by South Korean news media reports that suggested the North kept the complex open to obtain hard currency.

In another development, some of North Korea’s main government-run Web sites were disabled on Saturday in what news media reports said were cyber attacks.

The disabled sites included those of Naenara, the government’s official Web portal; Air Koryo, the state-run airline; and Voice of Korea, Pyongyang’s international broadcast outlet.

North Korea Tech, a Web site that monitors Internet activities on the Korean Peninsula, said the problems appeared “to be part of a loosely coordinated effort by hackers to target North Korean sites.” By late Saturday afternoon, North Korean officials had not confirmed any attacks on government-run Web sites.

The problems come as some analysts suspect that cyber attacks have become an increasingly frequent weapon in the intensified sparring between the Koreas, although each side denies hacking the other.

South Korean officials suspect that North Korea was behind cyber attacks on March 20 against three banks and the country’s two largest broadcasters. The attacks came five days after North Korea blamed South Korea and the US for cyber attacks that temporarily shut down some of its official Web sites, and warned of “consequences”.

North Korea has been angry ever since South Korea and the US started a joint military exercise in early March. Its bellicosity further escalated when the UN imposed more sanctions against it after its February 12 nuclear test.

North Korea has since declared an “all-out action” against Washington and Seoul and said that the armistice that stopped the Korean War in 1953, as well as all nonaggression agreements with South Korea were nullified.

North Korean leader, Kim Jong-un, ordered all his missile units to be on standby and if provoked, attack the US and South Korea with nuclear-tipped long-range missiles, although most analysts doubt the North has them.

A statement by South Korea’s military said that although the North Korean threats were not new, they “are unacceptable and harm the peace and stability of the Korean Peninsula.”

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