Pyongyang:
Stung by a surprise underwater attack, South Korea flexed its muscles on Thursday with anti-submarine drills and a US general offered strong words of support to South Korea.
Pyongyang, however, wasted little time in responding, saying it would launch "immediate physical strikes" against southern ships that enter its waters as tensions spiked further a week after Seoul blamed the North for torpedoing a warship.
Inter-Korean political and economic ties have been steadily deteriorating since the February 2008 inauguration of South Korean President Lee Myung-bak, who vowed a tougher line on the North and its nuclear programme.
But the sinking of the warship Cheonan and the deaths of 46 sailors in March have returned military tensions, and the prospect of armed conflict, to the fore.
Off the South's western coast, 10 warships, including a 3,500-ton destroyer, fired artillery and other naval guns and dropped anti-submarine bombs during a one-day exercise to boost readiness, the navy said. It was the first such drill since the Cheonan disaster, a navy official said on condition of anonymity, citing department policy.
South Korea also is planning two major joint military drills with the US by July in a display of force intended to deter future aggression by North Korea, according to South Korea's Joint Chiefs of Staff.
The North has denied it attacked the Cheonan and says attempts to punish it would lead to war.
On Thursday, it announced that in retaliation for the South's moves it would scrap an accord aimed at preventing accidental naval clashes with the South.
The agreement had covered disputed western waters where the Koreas have fought three bloody sea battles and near where the Cheonan sank.
"The KPA will ... start examining the closure of the military communications liaison offices in the eastern and western coastal areas and the total suspension of the overland passage concerning the Kaesong Industrial Zone, etcetera, for the present," North state broadcaster KRT said on Thursday.
North Korea also threatened "merciless counteractions" against the psychological warfare campaign that the South announced it will resume after a six-year suspension, referring to Seoul's plans to restart broadcasts across the demilitarised zone.
Earlier in the day, South Korean workers queued at the border with North Korea, before heading off to work at a joint industrial park in the North Korean border town of Kaesong, the last remaining major inter-Korean reconciliation project.
On Wednesday, the North expelled eight South Korean government officials from the joint factory park, in retaliation for Seoul blaming Pyongyang for a torpedo attack that sank a South Korean warship.
On Thursday trucks and cars were also passing across the border to deliver goods to the joint industrial zone.
Meanwhile, thousands of demonstrators gathered in downtown Seoul to protest against North Korean policies against the South on Thursday.
Waving the South Korean flag, they rallied, and beat inflatable doll effigies of former North Korean leader Kim Il-Sung and his son, the current leader, Kim Jong-Il.
Protesters smashed plates using the traditional Korean martial art of Taekwondo and sang patriotic Korean songs.
The prospect of another eruption of serious fighting has been constant on the Korean peninsula since the Korean War ended.
But it had been largely out of focus in the past decade as North and South Korea took steps to end enmity and distrust, such as launching joint economic projects and holding two summits.
The sinking of the warship, however, clearly caught South Korea, which has a far more modern and advanced military than its impoverished rival, off guard.
Now, South Korean and US militaries are taking pains to warn the North that such an attack will not happen again.
South Korean media reported earlier on Thursday that the US-South Korean combined forces command led by Sharp raised its surveillance level, called Watch Condition, up a level from 3 to 2. Level 1 is the highest.
The increased alert level means US spy satellites and U-2 spy planes would intensify their reconnaissance of North Korea, the JoongAng Ilbo newspaper said, citing an unidentified South Korean official.
The South Korean and US militaries would not confirm any reports on changes to the level.
If confirmed, it would be the first change since North Korea carried out a nuclear test in May 2009, a South Korean Joint Chiefs of Staff officer said on condition of anonymity, citing department policy.
A South Korean Defence Ministry official said Seoul will "resolutely" deal with the North's measures announced on Thursday, though did not elaborate.
He spoke on condition of anonymity, citing department policy.
South Korea's military said there were no signs of unusual activity by North Korean troops.
Meanwhile, ahead of Memorial day, members of the US armed forces paid their respects to the fallen service men and women from the Korean War, and to sailors from the Cheonan.
Service men and women from the US Army, US Air force and US Navy carried flags and marched to honour the war dead.
General Walter L. Sharp, a commander of the ROK-US Combined Forces Command, called on North Korea to abide by past agreements.
"We call on North Korea to cease all acts of provocation and to live up to with terms of past agreements including the armistice agreement," Sharp said.
The US fought on the South Korean side during the 1950-53 Korean War, which ended in an armistice, not a peace treaty.
North Korea has long demanded a permanent peace agreement.
The US stations 28,500 troops in South Korea, a legacy of the Korean War.
Pyongyang, however, wasted little time in responding, saying it would launch "immediate physical strikes" against southern ships that enter its waters as tensions spiked further a week after Seoul blamed the North for torpedoing a warship.
Inter-Korean political and economic ties have been steadily deteriorating since the February 2008 inauguration of South Korean President Lee Myung-bak, who vowed a tougher line on the North and its nuclear programme.
But the sinking of the warship Cheonan and the deaths of 46 sailors in March have returned military tensions, and the prospect of armed conflict, to the fore.
Off the South's western coast, 10 warships, including a 3,500-ton destroyer, fired artillery and other naval guns and dropped anti-submarine bombs during a one-day exercise to boost readiness, the navy said. It was the first such drill since the Cheonan disaster, a navy official said on condition of anonymity, citing department policy.
South Korea also is planning two major joint military drills with the US by July in a display of force intended to deter future aggression by North Korea, according to South Korea's Joint Chiefs of Staff.
The North has denied it attacked the Cheonan and says attempts to punish it would lead to war.
On Thursday, it announced that in retaliation for the South's moves it would scrap an accord aimed at preventing accidental naval clashes with the South.
The agreement had covered disputed western waters where the Koreas have fought three bloody sea battles and near where the Cheonan sank.
"The KPA will ... start examining the closure of the military communications liaison offices in the eastern and western coastal areas and the total suspension of the overland passage concerning the Kaesong Industrial Zone, etcetera, for the present," North state broadcaster KRT said on Thursday.
North Korea also threatened "merciless counteractions" against the psychological warfare campaign that the South announced it will resume after a six-year suspension, referring to Seoul's plans to restart broadcasts across the demilitarised zone.
Earlier in the day, South Korean workers queued at the border with North Korea, before heading off to work at a joint industrial park in the North Korean border town of Kaesong, the last remaining major inter-Korean reconciliation project.
On Wednesday, the North expelled eight South Korean government officials from the joint factory park, in retaliation for Seoul blaming Pyongyang for a torpedo attack that sank a South Korean warship.
On Thursday trucks and cars were also passing across the border to deliver goods to the joint industrial zone.
Meanwhile, thousands of demonstrators gathered in downtown Seoul to protest against North Korean policies against the South on Thursday.
Waving the South Korean flag, they rallied, and beat inflatable doll effigies of former North Korean leader Kim Il-Sung and his son, the current leader, Kim Jong-Il.
Protesters smashed plates using the traditional Korean martial art of Taekwondo and sang patriotic Korean songs.
The prospect of another eruption of serious fighting has been constant on the Korean peninsula since the Korean War ended.
But it had been largely out of focus in the past decade as North and South Korea took steps to end enmity and distrust, such as launching joint economic projects and holding two summits.
The sinking of the warship, however, clearly caught South Korea, which has a far more modern and advanced military than its impoverished rival, off guard.
Now, South Korean and US militaries are taking pains to warn the North that such an attack will not happen again.
South Korean media reported earlier on Thursday that the US-South Korean combined forces command led by Sharp raised its surveillance level, called Watch Condition, up a level from 3 to 2. Level 1 is the highest.
The increased alert level means US spy satellites and U-2 spy planes would intensify their reconnaissance of North Korea, the JoongAng Ilbo newspaper said, citing an unidentified South Korean official.
The South Korean and US militaries would not confirm any reports on changes to the level.
If confirmed, it would be the first change since North Korea carried out a nuclear test in May 2009, a South Korean Joint Chiefs of Staff officer said on condition of anonymity, citing department policy.
A South Korean Defence Ministry official said Seoul will "resolutely" deal with the North's measures announced on Thursday, though did not elaborate.
He spoke on condition of anonymity, citing department policy.
South Korea's military said there were no signs of unusual activity by North Korean troops.
Meanwhile, ahead of Memorial day, members of the US armed forces paid their respects to the fallen service men and women from the Korean War, and to sailors from the Cheonan.
Service men and women from the US Army, US Air force and US Navy carried flags and marched to honour the war dead.
General Walter L. Sharp, a commander of the ROK-US Combined Forces Command, called on North Korea to abide by past agreements.
"We call on North Korea to cease all acts of provocation and to live up to with terms of past agreements including the armistice agreement," Sharp said.
The US fought on the South Korean side during the 1950-53 Korean War, which ended in an armistice, not a peace treaty.
North Korea has long demanded a permanent peace agreement.
The US stations 28,500 troops in South Korea, a legacy of the Korean War.
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