By Kim Young-jin
Seoul is closely monitoring activities at a North Korean nuclear site amid signs that Pyongyang is preparing for a third nuclear test, government sources said Sunday.
The vigilance comes after South Korean and U.S. intelligence authorities spotted the North digging additional tunnels at the Musudan-ri Launch Facility for a possible underground atomic test, a source told Yonhap News Agency.
"It's obvious that North Korea is preparing for a third nuclear test," the source said on condition of anonymity, adding that multiple tunnels are being dug so that Pyongyang can choose the best one to conduct the test.
The facility, located in Punggye-ri in the country’s northwest corner, is the site of the North’s previous tests in 2006 and 2009.
The development heightens concern over the North’s nuclear and missile programs, for which the isolated state is already sanctioned by the international community.
In November last year, Pyongyang disclosed to a visiting American scientist a modern uranium enrichment program that experts fear could be converted to produce nuclear weapons.
"It's unclear whether the North will conduct a plutonium-fueled nuclear test or uranium-fueled one," the source said.
"But it's likely to opt for the plutonium-based program as it has already revealed the existence of a modern uranium enrichment facility and expects strong opposition from China.”
Last week, reports surfaced that it had completed a second ballistic missile launch site in the country’s northwest, sparking concern over the North’s ongoing quest for intercontinental ballistic missile (ICBM) capability and the possibility of a fresh missile launch.
The North, which has not publically acknowledged the new site, has previously conducted long-range missile tests on three occasions, claiming the launches were aimed at sending a satellite into orbit. They were seen as partial successes.
A military source said the Joint Chiefs of Staff is preparing to deal with the possibility of both a nuclear test and long-range missile launch.
Tension between the Koreas has soared over the last year, stoked by the North’s sinking of the warship Cheonan in November and its unprovoked shelling of Yeonpyeong Island eight months later. A total of 50 people were killed in the attacks.
The sides held working-level talks earlier this month in a bid to reduce tensions and pave the way for high-level military dialogue. But the negotiations collapsed as the sides failed to agree on the agenda and other procedural issues regarding further talks.
Senior officials in Seoul and Washington have in recent weeks expressed growing concern over the possibility of the North resorting to provocative behavior as it attempts to hand power from leader Kim Jong-il to his youngest son, Kim Jong-un.
Its ability to secure aid for its populace will help determine the success of the succession, analysts say.
