Roundup: S. Korea deeply worried about DPRK's test-firing of submarine missile

South Korea's military expressed a deep worry Monday about the Democratic People's Republic of Korea (DPRK)'s test-firing of a ballistic missile from its submarine.

"Our military is deeply and seriously worried about the underwater test-firing of a ballistic missile conducted by North Korea (DPRK) last week," Defense Ministry spokesman Kim Min-seok told a regular press briefing.

Kim urged Pyongyang to immediately stop developing the submarine-launched ballistic missile (SLBM) that would destabilize the Korean Peninsula and the Northeast Asian region.

The DPRK's official KCNA news agency reported Saturday that it succeeded in test-firing a ballistic missile from a submarine, which was "officially" overseen by top leader Kim Jong Un.

The South Korean military said Pyongyang had "unofficially" test-fired similar missiles several times in the past.

It was believed to be an initial phase of the SLBM, or an underwater launch of a ballistic missile, the spokesman said, noting that it would take four to five years to complete the development and deployment of these missiles given the cases of advanced countries.

The ballistic missile, named "North Star" or Bukgeukseong in Korean, was fired from a new DPRK submarine. The 2,000-ton sub is expected to be deployed in two to three years.

The DPRK's SLBM could mean more powerful nuclear threats to the U.S. mainland as well as South Korea because the fully-developed SLBM would mean a DPRK submarine secretly sailing underwater to the U.S. waters and firing ballistic missiles to strike major military facilities and the mainland.

The DPRK's third nuclear test in February 2013 raised concerns for its miniaturizing nuclear devices. If Pyongyang succeeds in producing a nuclear warhead that can be mounted onto the SLBM, its nuclear operational capability would become a real threat.

Pyongyang is known to have developed its own intercontinental ballistic missile (ICBM) called KN-08, but it hasn't test-fired the missile yet. Not confirmed was whether the DPRK has a re-entry technology, a basis for developing an SLBM with a range of more than 2,400 km.

While the ICBMs can be detected before launches by surveillance satellites and early warning aircraft, the SLBM is very hard to detect and preemptively strike as the submarine is an underwater weapon that cannot be detected by existing missile defense radars. It could mean an overhaul in South Korea's missile defense system.

The South Korean military said it can detect the DPRK submarine with existing U.S.-South Korea joint military assets for intelligence, surveillance and reconnaissance (ISR) and strike the sub with its own missiles.

But, a South Korean military expert on submarines was quoted by local media as saying that a submarine cannot be easily detected as the military insisted, worrying that it would be hard to strike the SLBM and the sub because it would be hard to detect where the sub sails.

Spokesman Kim said that if the DPRK submarine sails underwater, it would be hard to find where it is, noting that the submarine could be tackled before going underwater. Endi