"There have been continuous activities in Punggyeri since the nuclear test on October 9," a military source was quoted as saying by Yonhap.

"However, it remains unclear whether these activities are related with a second nuclear test or North Koreans are just faking it," the source said.

A defence ministry spokesman declined to comment on the reports.

The Science and Technology Ministry said Punggyeri, some 350 kilometers (219 miles) northeast of Pyongyang, was believed to be the place where the nuclear test was carried out.

Earlier reports said the test appeared to have been conducted at Hwadaeri, some 30 kilometers southwest of Punggyeri.

Punggyeri is where vehicle movements and the unloading of large reels of cable were spotted by satellite images last month, prompting speculation that a nuclear test was being prepared.

Chung Hyung-Keun, an opposition Grand National Party lawmaker who serves on parliament's intelligence committee, has said that the first nuclear test was carried out in one of two horizontal tunnels dug into hills in Punggyeri.

"A shelter was built outside the other tunnel and some 30 to 40 people have been working there," Chung said on a radio talk show on Thursday last week.

The October 9 test caused a global uproar with the UN Security Council issuing a resolution imposing economic sanctions aimed at reining in Pyongyang's weapons programme.

earlier related report
NKorea accuses US, SKorea of preparing for nuclear war
Seoul (AFP) Oct 27 - North Korea on Friday claimed the United States and South Korea were planning a nuclear war against the communist state, accusing them of devising a war plan and stocking up on the latest weapons.

"The madcap nuclear war moves against the DPRK (North Korea) are extremely reckless proactive acts that make the nuclear issue on the Korean peninsula all the more difficult to resolve and drive the situation to its worst," the Korea National Peace Committee said in a statement carried on the North's KCNA news agency.

The statement also said the North's own nuclear test was part of preparations to defend itself against an US attack. It claimed US outrage over the regime's test was a smokescreen for its own war plans.

"The people and its army are prepared for any provocations, any nuclear war moves," it said.

It warned South Korea against relying on the United States for protection which would only make the country more vulnerable to an attack.

North Korea carried out its first nuclear test on October 9, sparking international condemnation and UN Security Council sanctions.

South Korea says it will consider revising its policy of reconciliation toward the North to bring it more in line with international sanctions.

Under a joint military alliance, the United States has reaffirmed its commitment to extend a nuclear umbrella over South Korea amid an escalating nuclear threat from North Korea.

Seoul reportedly wants Washington, which withdrew all its nuclear weapons from the Korean peninsula in 1991, to elaborate on what types of tactical nuclear weapons could be provided under the deterrent strategy.

South Korea gave up its quest for nuclear weapons in the 1970s under strong US pressure.

The US has stationed tens of thousands of troops in South Korea ever since the 1950-53 war sparked by an invasion from the North.

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