North Korea said on Saturday it was entering a "state of war" with South Korea, its latest bout of angry rhetoric directed at Seoul and Washington, but the South brushed off the statement as little more than tough talk.
The North also threatened to shut down an industrial zone it operates jointly with the South near the heavily armed border between the two sides if Seoul continued to say the complex was being kept running for money.
The two Koreas have been technically in a state of war for six decades under a truce that ended their 1950-53 conflict. Despite its threats, few people see any indication Pyongyang will risk a near-certain defeat by re-starting full-scale war.
"From this time on, the North-South relations will be entering the state of war and all issues raised between the North and the South will be handled accordingly," a statement carried by the North's official KCNA news agency said.
KCNA said the statement was issued jointly by the North's government, ruling party and other organizations.
There was no sign of unusual activity in the North's military to suggest an imminent aggression, a South Korean defense ministry official said.
The North has been threatening to attack the South and U.S. military bases almost on a daily basis since the beginning of March, when U.S. and South Korean militaries started routine drills that have been conducted for decades without incident.
Many in the South have regarded the North's willingness to keep open the Kaesong industrial zone, located just a few miles (km) north of the border, as a sign that Pyongyang will not risk losing a lucrative source of foreign currency by mounting a real act of aggression.
The Kaesong zone is a vital source of hard currency for the impoverished state and hundreds of South Korean workers and vehicles enter daily after crossing the armed border.
"If the puppet traitor group continues to mention the Kaesong industrial zone is being kept operating and damages our dignity, it will be mercilessly shut off and shut down," KCNA quoted an agency that operates Kaesong as saying in a statement.
The threat to shut it down could sharply escalate tensions because it would suspend a symbolic joint project run by the rivals. It could also trap hundreds of South Korean workers and managers of the 123 firms that have factories there.
The North has previously suspended operations at the factory zone at the height of political tensions with the South, only to let it resume operations later.
The project has been kept running despite the North's move on Wednesday to cut off a military hotline used to process the hundreds of workers and vehicles that cross the Demilitarized Zone border.
"We have been exercising extreme restraint considering the plight of medium and small companies whose livelihood depends on the Kaesong industrial project as an immediate shutdown will drive them to bankruptcy and people jobless," KCNA quoted the agency as saying.
The South's Unification Ministry, which handles political ties with the North, said earlier in the day that the Kaesong industrial park was operating as normal with workers and vehicles crossing the border both says.
"North Korea's statement today (on entering a state of war) ... is not a new threat but is the continuation of provocative threats," a ministry statement said.
North Korean leader Kim Jong-un on Friday signed off on an order putting its missile units on standby to attack U.S. military bases in the South and the Pacific, after the United States flew two nuclear-capable stealth bombers over the Korean peninsula in a rare show of force.
U.S. officials said the B-2 bombers were on a diplomatic sortie aimed at reassuring allies South Korea and Japan and were also aimed at trying to nudge Pyongyang back to dialogue, although there was no guarantee Kim would get the message as intended.
The South Korean government brushed off the North's latest statement on entering a state of war, saying there was nothing fresh in it to cause greater alarm. South Koreans went about with daily lives as they have done through March under the North's constant threat of attack.