North tests SLBM days after ballistic missile launch, remains silent

North Korea fired a submarine-launched ballistic missile (SLBM) Saturday just four days after conducting a ballistic missile test. The apparent SLBM launch was detected at 2 p.m. Saturday off of the east coast city of Sinpo, according to..

A passerby watches previous reports of an SLBM launch in the waiting room of Seoul Station in Jung District, central Seoul, on Saturday. [NEWS1]

North Korea fired a submarine-launched ballistic missile (SLBM) Saturday just four days after conducting a ballistic missile test.

The apparent SLBM launch was detected at 2 p.m. Saturday off of the east coast city of Sinpo, according to the Joint Chiefs of Staff (JCS). The missile flew 600 kilometers (372 miles) and reached an apogee of 60 kilometers.

It is the first SLBM test by North Korea since a mini-SLBM was fired on Oct. 19. Unusual submarine movements have been detected recently near Sinpo by the military, which has been monitoring the area for signs of SLBM launches.

Although North Korean state media did not report the event, South Korean military experts have determined that the SLBM launched Saturday also seems to have been a mini-SLBM. Experts judged it to be an improved version of the KN-23 — a North Korean version of Iskander, a Russian mobile short-range ballistic missile system — due to its flight characteristics.

"The performance must have improved. It was not just a simple modification," said former National Defense University professor Kwon Yong-soo. "That would make interception more difficult."

SLBMs can be launched from submerged submarines.

North Korea fired a ballistic missile last Wednesday, although it did not report on the launch afterwards.

North Korea's recent missile tests are being viewed as "calculated provocation" with the inauguration of President-elect Yoon Suk-yeol on Tuesday and a South Korea-U.S. summit on May 21, according to press reports.

Observers predict that North Korea will gradually raise the level of provocation ahead of the events and top off the provocations with high-intensity weapons tests, such the firing of an intercontinental ballistic missile (ICBM) or a seventh nuclear test.

The provocations, the reports continue, seem to be shows of force, tests for the new government and efforts to gain a stronger negotiating position if dialogue resumes.

In the previous 14 weapons tests this year, North Korea fired a wide range of projectiles, including hypersonic missiles, KN-23s, KN-24s, cruise missiles, ICBMs (the Hwasong-15 and Hwasong-17) and a close-range ballistic missile (CRBM).

The silence from the North is unusual. When it launches a missile, it usually confirms the launch and releases details about the test, including photographs, the next day. As of press time Sunday, no information has been published.

"It seems that North Korea did not report on the missile test on Wednesday to get attention," said Yang Moo-jin, a professor of North Korean politics at the University of North Korean Studies.

The test may also have failed to achieve the desired results.

"The possibility that the launch on Wednesday failed should be kept open," said Lim Eul-chul, a professor of North Korean studies at the Institute for Far Eastern Studies at Kyungnam University.

The Blue House held an emergency meeting of the National Security Council's (NSC) standing committee presided over by National Security Office Director Suh Hoon on Saturday.

"This is a violation of UN Security Council resolutions and has harmed the Korean Peninsula, the region and the international community," the NSC's joint statement said.

The U.S. condemned North Korea's SLBM launch and reaffirmed its security commitments to South Korea and other allies.

"The launch Saturday, like other recent launches, is in violation of multiple UN Security Council resolutions and is a threat to North Korea's neighbors and the international community," the U.S. State Department told Yonhap News Agency. "We remain open to a diplomatic approach to North Korea and ask it to engage in dialogue."

"Our security commitments to South Korea and Japan are ironclad."

BY CHUNG YOUNG-GYO, LIM JEONG-WON [lim.jeongwon@joongang.co.kr]